Category: Class 10

Students can download 10th Science Chapter 14 Transportation in Plants and Circulation in Animals Questions and Answers, Notes, Samacheer Kalvi 10th Science Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

Tamilnadu Samacheer Kalvi 10th Science Solutions Chapter 14 Transportation in Plants and Circulation in Animals

Samacheer Kalvi 10th Science Transportation in Plants and Circulation in Animals Text Book Back Questions and Answers

I. Choose the best answer:

Question 1.
Active transport involves:
(a) movement of molecules from lower to higher concentration
(b) expenditure of energy
(c) it is an uphill task
(d) all of the above
Answer:
(d) all of the above

Question 2.
Water which is absorbed by roots is transported to aerial parts of the plant through ______.
(a) cortex
(b) epidermis
(c) phloem
(d) xylem.
Answer:
(d) xylem.

Question 3.
During transpiration there is loss of:
(a) carbon dioxide
(b) oxygen
(c) water
(d) none of the above
Answer:
(c) water

Question 4.
Root hairs are ______.
(a) cortical cell
(b) projection of the epidermal cell
(c) unicellular
(d) both b and c.
Answer:
(b) projection of the epidermal cell

Question 5.
Which of the following process requires energy?
(a) active transport
(b) diffusion
(c) osmosis
(d) all of them
Answer:
(a) active transport

Question 6.
The wall of the human heart is made of ______.
(a) Endocardium
(b) Epicardium
(c) Myocardium
(d) All of the above.
Answer:
(d) All of the above.

Question 7.
Which is the sequence of correct blood flow?
(a) ventricle – atrium – vein – arteries
(b) atrium – ventricle – veins – arteries
(c) atrium – ventricle – arteries – vein
(d) ventricles – vein – atrium – arteries
Answer:
(c) atrium – ventricle – arteries – vein

Question 8.
A patient with blood group O was injured in an accident and has blood loss. Which blood group the doctor should effectively use for transfusion in this condition?
(a) O group
(b) AB group
(c) A or B group
(d) all blood group.
Answer:
(d) all blood group.

Question 9.
‘Heart of heart’ is called:
(a) SA node
(b) AV node
(c) Purkinje fibres
(d) Bundle of His
Answer:
(a) SA node

Question 10.
Which one of the following regarding blood composition is correct?
(a) Plasma – Blood + Lymphocyte
(b) Serum – Blood + Fibrinogen
(c) Lymph – Plasma + RBC + WBC
(d) Blood – Plasma + RBC + WBC + Platelets.
Answer:
(d) Blood – Plasma + RBC+ WBG + Platelets.

II. Fill in the blanks:

1. ……….. involves evaporative loss of water from aerial parts.
2. Water enters the root cell through a ………. plasma membrane.
3. Structures in roots that help to absorb water are …………
4. Normal blood pressure is …………
5. The normal human heartbeat rate is about ……….. time per minute.

Answer:

1. Transpiration
2. Semipermeable
3. Root hairs
4. 120 mm / 80 mm Hg
5. 72 – 75 times

III. Match the following:

Section – I

Answer:
A. (ii)
B. (i)
C. (iv)
D. (iii)

Section – II

Answer:
A. (iv)
B. (i)
C. (ii)
D. (iii)
E. (viii)
F. (vii)
G. (v)
H. (vi)

IV. State whether True or False. If false write the correct statement:

1. The phloem is responsible for the translocation of food.
2. Plants lose water by the process of transpiration.
3. The form of sugar transported through the phloem is glucose.
4. In apoplastic movement the water travels through the cell membrane and enter the cell.
5. When the guard cells lose water the stoma opens.
6. Initiation and stimulation of heart beat take place by nerves.
7. All veins carry deoxygenated blood.
8. WBC defend the body from bacterial and viral infections.
9. The closure of the mitral and tricuspid valves at the start of the ventricular systole produces the first sound ‘LUBB’.

Answer:

1. True
2. True
3. False – The form of sugar transported through the phloem is sucrose.
4. False – Apoplastic movement does not involve crossing the cell membrane.
5. False – When the guard cells lose water the stoma closes.
6. False – Initiation and stimulation of heart beat take place by Sino-atrial node.
7. False – All veins carry deoxygenated blood except the pulmonary veins,
8. True
9. True.

V. Answer in a word or sentence:

Question 1.
Name two layered protective covering of human heart.
Answer:
Pericardium is the two layered protective covering of human heart.

Question 2.
What is the shape of RBC in human blood?
Answer:
The shape of RBC in human blood is biconcave and disc – shaped.

Question 3.
Why is the colour of the blood red?
Answer:
The blood is red in colour due to the presence of respiratory pigment – haemoglobin.

Question 4.
Which kind of cells are found in the lymph?
Answer:
Lymphocytes in the lymph, which defend the body from infection.

Question 5.
Name the heart valve associated with the major arteries leaving the ventricles.
Answer:
Aortic valve present at the base of aorta.

Question 6.
Mention the artery which supplies blood to the heart muscle.
Answer:
Coronary arteries.

VI. Short Answer Questions.

Question 1.
What causes the opening and closing of guard cells of stomata during transpiration?
Answer:
The general mechanism of stomatal movement is based on entry and exit of water molecules in guard cells. When the turgidity increases within the guard cells the stomata open. When the guard cells lose water it becomes flaccid and the stomata closes.

Question 2.
What is cohesion?
Answer:
The force of attraction between molecules of water is called Cohesion.

Question 3.
Trace the pathway followed by water molecules from the time it enters a plant root to the time it escapes into the atmosphere from a leaf.
Answer:
Soil → root hair → cortex → endodermis → Pericycle → xylem → stem → leaves.

Question 4.
What would happen to the leaves of a plant that transpires more water than its absorption in the roots?
Answer:
When transpiration exceeds than water absorption by roots, the plant dehydrates. It affects plant processes such as growth, Photosynthesis and transpiration.

Question 5.
Describe the structure and working of the human heart.
Answer:
The heart is thick muscular organ located in the thoracic cavity. It is covered by a two layered sac called pericardium. The heart is four chambered with two auricles and two ventricles. Right Auricle receives deoxygenated blood from superior and inferior vena cava and passes to right ventricles from right ventricles impure blood passes to pulmonary artery and reaches the lungs.

Question 6.
Why is the circulation in man referred to as double circulation?
Answer:
The blood circulates twice, through the heart in one complete cycle, in the circulation of blood in man. So it is called double circulation.

Question 7.
What are heart sounds? How are they produced?
Answer:
‘Lubb’ and ‘Dupp’ are the sounds of the heart. ‘Lubb’ sound is produced by the ventricle- contraction. It arises due to closing of mitral and tricuspid valve.
‘Dupp’ is produced by ventricular diastole. This arises due to the closing of the semi-lunar valves of two auricles.

Question 8.
What is the importance of valves in the heart?
Answer:
The valves are the muscular flaps, that regulate the flow of blood in a single direction and prevent backflow of blood.

Question 9.
Who discovered Rh factor? Why was it named so?
Answer:
Landsteiner and Wiener discovered Rh factor of blood in 1940. Rh factor is a protein CD antigen present on the surface of the red blood cells in majority of humans. This protein is similar to the protein present in Rhesus monkey, hence the term Rh.

Question 10.
How are arteries and veins structurally different from one another?
Answer:

Question 11.
Why is the Sinoatrial node called the pacemaker of the heart?
Answer:
Sinoatrial node is called the pacemaker of the heart because it is capable of initiating impulse, which can stimulate the heart muscles to contract.

Question 12.
Differentiate between systemic circulation and pulmonary circulation.
Answer:

Question 13.
The complete events of the cardiac cycle last for 0.8 sec. What is the timing for each event?
Answer:

1. Atrial Systole: Contraction of auricles (0.1 sec)
2. Ventricular Systole: Contraction of ventricles (0.3 sec)
3. Ventricular diastole: Relaxation of Ventricles (0.4 sec).

VII. Give reasons for the following statements:

Question 1.
Minerals cannot be passively absorbed by the roots.
Answer:
All minerals cannot be passively absorbed by the roots because, minerals are present in the soil as charged particles that cannot move across the cell membranes and the concentration of minerals in the soil is usually lower than the. concentration of minerals in the root. So, the minerals enter the root by active absorption through the cytoplasm of epidermal cells which needs energy.

Question 2.
Guard cells are responsible for opening and closing of stomata.
Answer:
Guard cells are responsible for the opening and closing of stomata because, during transpiration, the movement of ions (Potassium) in and out of the guard cells causes the opening and closing of Stomata. When the water moves inside the guard cells, causing them to swell up and become turgid making the stomata open. When guard cells cause water to move out of the cell and make guard cells shrunk and stomata pores close.

Question 3.
The movement of substances in the phloem can be in any direction.
Answer:
Phloem transports food from the source to sink. The source is part in which plant synthesize food, sink is the part that needs or stores food. Since the source-sink relationship is variable, the direction of movement in the Phloem can be upwards or downwards, i.e., bidirectional.

Question 4.
Minerals in the plants are not lost when the leaf falls.
Answer:
Minerals like Phosphorus, Sulphur, Nitrogen and Potassium are remobilised in the soil from older dying leaves to younger leaves. This phenomenon is seen in deciduous plants. So minerals in the plants are not lost, when the leaf falls.

Question 5.
The walls of the right ventricle are thicker than the right auricles.
Answer:
Because the right ventricle have to pump out the deoxygenated blood with force away from the heart through pulmonary artery to lungs.

Question 6.
Mature RBC in mammals does not have cell organelles.
Answer:
Mature RBC in mammals does not have cell organelles because

• The lack of Nucleus in RBC makes the cells, biconcave and disc – shaped. RBC involved in the transport of oxygen from lungs to tissues.
• They do not have cell organelles in order to accommodate maximum space for haemoglobin.
• The loss of endoplasmic reticulum allows more flexibility, for RBC to move through narrow capillaries.

VIII. Long Answer Questions:

Question 1.
How do plants absorb water? Explain.
Answer:
Water present in the soil must reach the xylem of roots. Root hair is in contact with soil water. Their cell wall is thin and water easily diffuses in the passage of water from the soil to leaf is
Soil water → Root hair → Epidermis → Cortex → Endodermis → Pericycle → Xylem → Stem and leaf.
Once water is absorbed by the root hairs, it can move deepers into root layers by two pathways. Apoplast and Symplast.

1. Apoplast : This is the non living path in plants. It occurs through the intercellular spaces and walls of the cells. This movement dependent on the gradient.
2. Symplast : This is the living passage. The movement of water from cell to cell through plasmodesmato and cytoplasm, Movement is again down a potential gradient.

Question 2.
What is transpiration? Give the importance of transpiration.
Answer:
Transpiration is the evaporation of water in plants through stomata in the leaves.
Importance of Transpiration

• Creates transpirational pull for the transport of water.
• Supplies water for photosynthesis.
• Transports minerals from the soil to all parts of the plant.
• Cools the surface of the leaves by evaporation.
• Keeps the cells turgid; hence, maintains their shape.

Question 3.
Why are leucocytes classified as granulocytes and agranulocytes? Name each cell and mention its functions.
Answer:
Depending on the presence and absence of granules, leucoytes are divided into two types Granulocytes and Agranulocytes.
Granulocytes : They are characterised by the presence of granules in cytoplasm. The granulocytes include neutrophils, eosinophils and basophils.

1. Neutrophils : They constitute about 60-65% of total WBC’s. They are large and have many lobed nucleus. They are phagocytic in nature and appear in large,number in and around the infected tissue.
2. Eosinophils : They have bilobed nucleus and constitute about 2-3% of total WBC’s. Eosinophil increase during certain types of parasitic infection and allergic reaction. It bring about detoxification of toxin.
3. Basophils: Basophil have lobed nucleus. They form 0.5 – 1.0% of the total leucocytes. They release chemicals during the process of inflammation.

Agranulocytes : They are characterised by the absence of granules in the cytoplasm. These are of two types Lymphocytes and Monocytes.

1. Lymphocytes: These are about 20-25% of the total leucocytes. They produce antibodies during bacterial and viral infections.
2. Monocytes: They are the largest leucocytes and amoeboid in shape. These cells form 5-6% of the total leucocytes. They are phagocytic and can engulf bacteria.

Question 4.
Differentiate between systole and diastole. Explain the conduction of the heartbeat.
Answer:
One complete contraction (Systole) and relaxation (diastole) of the atrium and ventricles of the heart constitutes Heartbeat. The human heart is myogenic. Contraction is initiated by the sino – atrial (SA) node, which is situated in the wall of the right atrium, near the opening of the superior vena cava. SA node is broader at the top and tapering below and made up of thin fibres.

SA node acts as the ‘pacemaker’ of the heart because it is capable of initiating impulse which can stimulate the heart muscles to contract. The impulse spreads like a wave of contraction over the right and left atrial wall, pushing the blood, through the atrioventricular valves into the ventricles and the same wave from SA node reaches the atrioventricular node (AV), to emit an impulse of contraction, spreading to the ventricular muscle, through the atrioventricular bundle and the Purkinje fibres. The expansion of the artery every time, the blood is forced into the arteries, is called pulse. Normal pulse rate ranges from 70 – 90 / min.

Question 5.
Enumerate the functions of blood.
Answer:

1. Transport of respiratory gases (Oxygen and CO₂).
2. Transport of digested food materials to the different body cells.
3. Transport of hormones.
4. Transport of nitrogenous excretory products like ammonia, urea and uric acid.
5. It is involved in protection of the body and defense against diseases.
6. It acts as buffer and also helps in regulation of pH and body temperature.
7. It maintains proper water balance in the body.

IX. Assertion and Reasoning:

Direction: In each of the following questions a statement of assertion (A) is given and a corresponding statement of reason (R) is given just below it. Mark the correct statement as.
(a) If both A and R are true and R is correct explanation of A.
(b) If both A and R are true but R is not the correct explanation of A.
(c) A is true but R is false.
(d) Both A and R are false.
1. Assertion: RBC plays an important role in the transport of respiratory gases.
Reason: RBC do not have cell organelles and nucleus.
Answer:
(a) If both A and R are true and R is correct explanation of A.

2. Assertion: Persons with AB blood group are called an universal recipients, because they can receive blood from all groups.
Reason: Antibodies are absent in persons with AB blood group.
Answer:
(a) If both A and R are true and R is correct explanation of A.

X. Higher Order Thinking Skills (HOTS):

Question 1.
When any dry plant material is kept in water, they swell up. Name and define the phenomenon involved in this change.
Answer:
The process is imbibition’. The type of diffusion in which a solid absorbs water and gets swelled up is Imbibition.

Question 2.
Why are the walls of the left ventricle thicker than the other chambers of the heart?
Answer:
The walls of the left ventricle are about three times thicker than the right ventricle. The left ventricle gives rise to the aorta, which carries oxygenated blood, to various organs of the body. The ventricle walls are thick because they have to pump out blood with force away from the heart.

Question 3.
Doctors use stethoscope to hear the sound of the heart. Why?
Answer:
A stethoscope is an instrument used to detect the sound produced by the internal organs of human body. It is an useful diagnostic tool to identify and localize health problems and diagnose disease.

Question 4.
How do the pulmonary artery and pulmonary vein differ in their function when compared to a normal artery and vein?
Answer:

• All arteries carry oxygenated blood, except pulmonary arteries, which carry deoxygenated blood from the right ventricle to the lungs.
• All veins carry deoxygenated blood, except pulmonary veins, which carry oxygenated blood from the lungs and to the left atrium of the Heart.

Question 5.
Transpiration is a necessary evil in plants. Explain.
Answer:
The water is lost from the leaves due to transpiration, pressure is created in, at the top to pull more water from the xylem to the leaves through the process of transpiration pull. This ensure the continuous flow of water from the roots of the leaves.

Samacheer Kalvi 10th Science Transportation in Plants and Circulation in Animals Additional Important Questions and Answers

I. Choose the correct answer:

Question 1.
Seed swells when placed in water due to:
(a) osmosis
(b) imbibition
(c) hydrolysis
(d) all of these
Answer:
(b) imbibition

Question 2.
Root hairs occurs in:
(a) Meristematic zone
(b) Cell elongation zone
(c) Cell maturation zone
(d) Old root
Answer:
(c) Cell maturation zone

The other name for Red blood corpuscles (RBC) is called ______.
Answer:
Erythrocytes.

Question 3.
Water in plants is transported by ascent of sap takes place through:
(a) cambium
(b) xylem
(c) phloem
(d) epidermis
Answer:
(b) xylem

Question 4.
Absorption of water is increased when:
(a) transpiration is increased
(b) photosynthesis is increased
(c) respiration is increased
(d) root pressure is increased
Answer:
(a) transpiration is increased

Question 5.
Opening of stomata is due to:
(a) Turgidity of guard cells
(b) Size of guard cells
(c) Number of guard cells
(d) Amount of CO₂ in the atmosphere.
Answer:
(a) Turgidity of guard cells

Question 6.
Guard cells help in:
(a) Fighting against infection
(b) Guttation
(c) Protecting against grazing
(d) Transpiration
Answer:
(d) Transpiration

Question 7.
Photosynthetic food material is transported in the form of:
(a) Glucose
(b) Sucrose
(c) Starch
(d) Fructose
Answer:
(b) Sucrose

Question 8.
Coronary artery supplies blood to:
(a) Mammary glands
(b) Rib muscles
(c) Skin
(d) Heart
Answer:
(d) Heart

Question 9.
All arteries carry oxygenated blood except:
(a) systematic
(b) hepatic
(c) pulmonary
(d) cardiac
Answer:
(c) pulmonary

Question 10.
The colour of lymph is:
(a) white
(b) pale yellow
(c) colourless
(d) milky
Answer:
(c) colourless

Question 11.
An artery can be distinguished from a vein in having:
(a) thicker wall
(b) elastic vessels
(c) no valves
(d) all of the above
Answer:
(d) all of the above

Question 12.
Purkinje fibres mainly help in contraction of:
(a) right auricle
(b) left auricle
(c) ventricles
(d) Aorta
Answer:
(c) ventricles

Question 13.
The ‘Lubb’ and ‘Dupp’ heart sound are due to:
(a) opening of heart valves
(b) action of papillary’ muscles
(c) closing of heart valves
(d) activity of pace maker
Answer:
(c) closing of heart valves

Question 14.
The closed circulatory system occurs in:
(a) cockroach
(b) fish
(c) mosquito
(d) house fly
Answer:
(b) fish

Question 15.
Normal pulse rate is:
(a) 80 mm Hg
(b) 120 mm Hg
(c) 40 mg Hg
(d) 90 mm Hg
Answer:
(d) 90 mm Hg

Question 16.
In the ABO system of blood groups, of both antigens are present but no antibody, the blood group of the individual would be?
(a) B
(b) O
(c) AB
(d) A
Answer:
(c) AB

Question 17.
Arteries are branches of:
(a) capillaries
(b) veins
(c) aorta
(d) none of these
Answer:
(c) aorta

Question 18.
Which type of WBCs are found in maximum number?
(a) Monocytes
(b) Basophils
(c) Eosinophils
(d) Neutrophils
Answer:
(d) Neutrophils

Question 19.
Which of the following are granular WBCs?
(a) Neutrophils, Basophils, Lymphocytes
(b) Eosinophil, Basophil, Monocytes
(c) Basophils, Monocytes, Lymphocytes
(d) Neutrophils, Eosinophil, Basophil
Answer:
(d) Neutrophils, Eosinophil, Basophil

Question 20.
RBCs are concerned with carriage of gases.
(a) CO₂
(b) O₂
(c) Respiratory
(d) CO₂ and SO₂
Answer:
(c) Respiratory

II. Fill in the blanks:

1. The contraction of heart is called ………..
2. Oxygenated blood is carried by ………..
3. Sphygmomanometer measures ………..
4. Heart of man is ………..
5. Pace maker of heart is ………..
6. The life span of RBC in human is ……… days.
7. Pulmonary artery carry ………….. blood.
8. ………. discovered the circulation of blood in man.
9. Semilunar valve is present at the base of ………….
10. Human heart beats ………. times in a minute at rest.
11. Red blood pigment is ………..
12. Transpiration helps in the absorption and ………… movement of water and minerals.
13. Water in plants is transported by ascent of sap takes place through ……….
14. The absorption water due to expenditure of energy is called ………….
15. In plants, the translocation of organic solutes takes place through ………….
Answer:
1. systole
2. pulmonary vein
3. blood pressure
4. myogenic
5. sino atrial node
6. 120
7. deoxygenated
8. William Harvey
9. Pulmonary artery
10. 72
11. Haemoglobin
12. upward
13. xylem
14. active absorption
15. phloem

III. Match the following:

Question 1.
Match the Column I with Column II.

Answer:
A. (iv)
B. (iii)
C. (i)
D. (ii)

Question 2.
Match the Column I with Column II.

Answer:
A. (iv)
B. (iii)
C. (i)
D. (v)
E. (ii)

IV. State whether true or false. If false write the correct statement:

1. The human heart beats 72 times per minute.
2. Right half of heart receives and pu mps off oxygenated blood.
3. Between right auricle and right ventricle seen Mitral valve.
4. The force of attraction between water molecule is cohesion.
5. By passive transport sucrose moves into the cells where it is utilised or stored.

Answer:

1. True
2. False – Right half of heart receives and pumps off deoxygenated blood.
3. False – Between right auricle and right ventricle seen tricuspid valve.
4. True
5. False – By active transport sucrose moves into the cells where it is utilised or stored.

V. Creative Question:

Question 1.
Origin of heart beat and its conduction is represented by:
(a) AV node → Bundle of His → SA node → Purkinje fibres
(b) SA node → Purkinje fibres → AV node → Bundle of His
(c) Purkinje fibres → Purkinje node → AV fibres → Bundle of His
(d) SA node → AV node → Bundle of His → Purkinje fibres
Answer:
(d) SA node → AV node → Bundle of His → Purkinje fibres

Question 2.
The cardiac pacemaker in a patient fails to function normally. The doctors find that an artificial pacemaker is to be grafted in him. It is likely that it will be drafted at the site of:
(a) Purkinje system
(b) Sinu atrial node
(c) Atrio ventricular node
(d) Atrio ventricular bundle
Answer:
(b) Sinu atrial node

Question 3.
Doctor use stethoscope to hear the sounds produced during each cardiac cycle. The second sound is heard when:
(a) AV node receives signal from SA node
(b) AV valves open up
(c) Ventricular walls vibrate due to rushing in of blood from atria
(d) Semi lunar valves close down after the blood flows into vessels from ventricles
Answer:
(d) Semi lunar valves close down after the blood flows into vessels from ventricles

VI. Assertion and Reason:

(a) If both the assertion and the reason are true and the reason is the correct explanation of assertion.
(b) If both the assertion and the reason are true, but the reason is not the correct explanation of the assertion.
(c) Assertion is true, but the reason is false.
(d) Assertion is false, but the reason is true.
1. Assertion: RBC impart red colour to the blood due to the presence of respiratory pigment haemoglobin.
Reason: The young RBC contain nucleus in man.
Answer:
(b) If both the assertion and the reason are true, but the reason is not the correct explanation of the assertion.

2. Assertion: Osmosis is the movement of solvent molecule from higher concentration to lower concentration.
Reason: Osmosis is the active movement of water.
Answer:
(c) Assertion is true, but the reason is false.

VII. Answer in a Sentence:

Question 1.
Name the components of circulatory system.
Answer:
The circulation system consists of the circulating fluids, the blood and lymph, the heart and the blood vessels namely arteries, veins and capillaries.

Question 2.
What is the Ascent of Sap?
Answer:
The upward movement of water and minerals from roots to different plant parts is called ascent of sap.

Question 3.
Mention the composition of plasma.
Answer:
Organic substances like protein, glucose, urea, enzyme, hormones, vitamins and minerals are present in plasma.

Question 4.
Define Adhesion?
Answer:
The force of attraction between molecules of different substances is called adhesion.

Question 5.
Why are auricles and ventricles separated by auricular and ventricular septum?
Answer:
The separation of chamber avoids mixing of oxygenated and deoxygenated blood.

Question 6.
What is Single Circulation?
Answer:
In fishes, amphibians and certain reptiles, the oxygenated and deoxygenated blood are mixed ‘ and pass through the heart only once, is called Single Circulation.

Question 7.
Name the instruments used to measure blood pressure.
Answer:
Sphygmomanometer is a clinical instruments used to measure blood pressure when a person is in a relaxed and resting condition. Normal blood pressure in human is 120 mm/ 80 mm Hg.

Question 8.
Which blood group is called as ‘Universal Donor’ and ‘Universal Recipient’.
Answer:
Person with ‘O’ blood group are called Universal Donor.
Person with ‘AB’ blood group are called Universal Recipient.

Question 9.
What is Pulse?
Answer:
During the expansion of the artery, every time, the blood is forced into the arteries is called pulse.

Question 10.
What is transpiration puil?
Answer:
Transpiration through stomata creates vacuum which creates a suction called transpiration pull.

Question 11.
What are Rh antibodies?
Answer:
Rh-negative persons do not have Rh antigen on the surface of RBC. Antibodies developed against this Rh antigen is called Rh antibodies.

Question 12.
What is Adhesion?
Answer:
The force of attraction between molecules of different substances is called . adhesion.

VIII. Short answer question:

Question 1.
What is blood pressure?
Answer:
Blood pressure is the force exerted during the flow of blood against the lateral walls of arteries. The blood pressure is high in the arteries gradually drop in the arterioles and capillaries and become very low in the veins. Blood pressure varies during conditions of physical exercise, anxiety, emotions, stress and sleep. Increase in blood pressure is known as hypertension and decrease in blood pressure is termed as hypotension.

Question 2.
Distinguish between open and closed circulation.
Answer:

Question 3.
Explain the phenomenon of Guttation.
Answer:
The Guttation is a phenomenon caused due to root pressure. It takes place through a specialized cells called hydathodes. Dews on the leaves of grass seen in the early morning, when the climate is humid and excess of water in the soil is an example of Guttation.

Question 4.
What is Coronary circulation?
Answer:
The supply of blood to the heart muscles is called as coronary circulation. Cardiac muscles receives oxygenated blood from coronary arteries that originate from the aortic arch. Deoxygenated blood from the cardiac muscles drains into the right atrium by the coronary sinuses.

IX. Long answer questions:

Question 1.
What is lymph? Write its functions.
Answer:
Lymph is a colourless fluid formed when plasma, proteins and blood cells escape into intercellular spaces in the tissues through the pores present in the walls of capillaries.
Functions of Lymph:

1. Supplies nutrition and oxygen to those parts where blood cannot reach.
2. It drains away excess tissue fluid and metabolites and returns proteins to the blood from tissue spaces.
3. The lymph also carries absorbed fats from small intestine to the blood. The lymphatic capillaries of intestinal villi (lacteals) absorb digested fats.
4. Lymphocytes in the lymph defend the body from infections.

Question 2.
(a) Name the main two components of blood.
(b) What does plasma contain?
Answer:
(a) 1. The fluid plasma
2. Formed elements (blood cells)

• RBC
• WBC
• Blood platelets

(b) Plasma is slightly alkaline, containing non – cellular substance, constitute 55 % of the blood. Organic substances like Proteins, Glucose, Urea, Enzymes, Hormones, Vitamins and Minerals are present in the Plasma.

Question 3.
Demonstrate the process of osmosis with thistle funnel.
Answer:
Aim : To demonstrate the process of osmosis, using Thistle funnel.
Materials Required : Beaker, Thistle funnel, semi permeable membrane, sucrose solution.
Procedure : A thistle funnel whose mouth is covered with a semipermeable membrane, is filled with sucrose solution. It is kept inverted in a beaker containing water.
Observation : The water will diffuse across the membrane due to osmosis and raise the level of the solution in the funnel.
Inference : Raise of liquid in the funnel indicates the process of osmosis.

Question 4.
Explain Double circulation.
Answer:
Diagrammatic representation of the double circulation.

Question 5.
Explain the steps involved in Ascent of sap.
Answer:
The upward movement of water, and minerals from roots to different plant parts is called ascent of sap. A number of factors play a role in ascent of sap and it takes places in following steps.
Root Pressure : Water from soil enters the root hairs due to osmosis. Root pressure is responsible for movement of water up to the base of the stem.

Capillary Action : Water or any liquid rises in a capillary tube because of physical forces, this phenomenon is called capillary action. In the same way, in stem water rises up to certain height because of capillary’ action.
Adhesion-cohesion of Water Molecules : Water molecules form a continuous column in the xylem because of forces of adhesion and cohesion among the molecules.
Cohesion : The force of attraction between molecules of water is called cohesion.
Adhesion : The force of attraction between molecules of different substances is called adhesion.Water molecules stick to a xylem because of force of adhesion.

Question 6.
Explain the causes of the sound of the Heart.
Answer:
The rhythmic closure and opening of the valves cause the sound of the heart.

• The first sound ‘LUBB’ is produced by the closure of the tricuspid and bicuspid valves, after the beginning of ventricular systole. It is a longer duration.
• The second sound ‘DUPP’ is produced by the closure of semilunar valves, at the end of ventricular systole. It is of short duration.

X. Higher Order Thinking Skills (HOTS)

Question 1.
An unconscious patient is rushed into the emergency room and need a fast blood transfusion. Because there is no time to check her medical history or determine her blood type, which type of blood should you as her doctor, give?
Answer:
O^+ve, it is universal donor. In O group individuals, Antigen A or B are absent on the surface of RBC. However the plasma contains both antibodies a and b.

Question 2.
What are the factors affecting the Ascent of Sap?
Answer:

• High Temperature
• Atmospheric Pressure
• Wind Velocity
• Low atmospheric humidity
• Soil water deficit.

Question 3.
Water vapour comes out from the plant leaf through the stomatal opening. Through the same stomatal opening carbon dioxide diffuses into the plant during photosynthesis. Reason out the above statements.
Answer:
Both processes can happen together because the diffusion co-efficient of water and CO₂ is different.

Question 4.
Write a few Strategies, to prevent heart disease.
Answer:

• Exercise for about 30 minutes every day.
• Smoking or use of Tobacco should be avoided.
• Eat a heart-healthy diet – Avoid too much of salt or sugar, use of a diet rich in Vegetables and Fruits.
• Maintain a healthy weight.
• Get enough quality sleep.
• Manage Stress.
• Get regular health screenings (B.P. monitoring, Cholesterol level, Diabetes Screening etc.).

XI. Give reason:

Question 1.
Valves are important in human heart. Give reason.
Answer:
The valves will prevent the back flow of blood.

Question 2.
During rainy season wooden door generally swells up – Give reason.
Answer:
It is due to imbibition. It is a type of diffusion in which a solid absorbs water and gets swelled up.

Question 3.
Para sympathetic neural signals affects the working of the heart. Give reason.
Answer:
It reduce both heart rate and cardiac output.

Question 4.
Grapes placed in salt solution shrink. Give reason.
Answer:
It is due to exosmosis.

Question 5.
Why WBC’s are known as phagocytes?
Answer:
WBC produce antibodies during bacterial and viral infection and engulf the germs.

Students can download 10th Science Chapter 13 Structural Organisation of Animals Questions and Answers, Notes, Samacheer Kalvi 10th Science Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

Tamilnadu Samacheer Kalvi 10th Science Solutions Chapter 13 Structural Organisation of Animals

Samacheer Kalvi 10th Science Structural Organisation of Animals Text Book Back Questions and Answers

I. Choose the best answer:

Question 1.
In leech locomotion is performed by:
(a) Anterior sucker
(b) Posterior sucker
(c) Setae
(d) None of the above
Answer:
(a) Anterior sucker

Question 2.
The segments of leech are known as _____.
(a) Metameres (somites)
(b) Proglottids
(c) Strobila
(d) All the above.
Answer:
(a) Metameres (somites).

Question 3.
Pharyngeal ganglion in leech is a part of:
(a) Excretory system
(b) Nervous system
(c) Reproductive system
(d) Respiratory system
Answer:
(b) Nervous system

Question 4.
The brain of leech lies above, the _____.
(a) Mouth
(b) Buccal Cavity
(c) Pharynx
(d) Crop.
Answer:
(c) Pharynx

Question 5.
The body of leech has:
(a) 23 segments
(b) 33 segments
(c) 38 segments
(d) 30 segments
Answer:
(b) 33 segments

Question 6.
Mammals are animals.
(a) Cold blooded
(b) Warm blooded
(c) Poikilothermic
(d) All the above
Answer:
(b) Warm blooded

Question 7.
The animals which give birth to young ones are _____.
(a) Oviparous
(b) Viviparous
(c) Ovoviviparous
(d) All the above.
Answer:
(d) All the above

II. Fill in the blanks:

1. The posterior sucker is formed by the fusion of the ………. segments.
2. The existence of two sets of teeth in the life of an animal is called ……….. dentition.
3. The anterior end of leech has a lobe-like structure called ………..
4. The blood sucking habit of leech is known as ………..
5. ………. separate nitrogenous waste from the blood in rabbit.
6. ……… spinal nerves are present in rabbit.

Answer:

1. last seven
2. diphyodont
3. anterior sucker
4. sanguivorous
5. Nephrons (kidney)
6. 37 pair

III. Identify whether the statements are True or False. Correct the false statement:

1. An anticoagulant present in saliva of leech is called heparin.
2. The vas deferens serves to transport the ovum.
3. The rabbit has a third eyelid called tympanic membrane which is movable.
4. Diastema is a gap between premolar and molar teeth in rabbit.
5. The cerebral hemispheres of rabbit are connected by band of nerve tissue called corpora quadrigemina.

Answer:

1. True
2. False – Vas deferens serves to transport the sperm.
3. True
4. False – The gap between the incisors and premolars.
5. False – The cerebral hemispheres of rabbit are connected by band of nerve tissue called corpora corpus callosum.

IV. Match columns I, II and III correctly:

Answer:

V. Answer in a sentence:

Question 1.
Give the common name of the Hirudinaria granulosa.
Answer:
The common name of Hirundinaria granulosa is Indian Cattle Leech.

Question 2.
How does leech respire?
Answer:
Leech respire through the skin.

Question 3.
Write the dental formula of rabbit.
Answer:
The dental formula of rabbit is \(\frac{2033}{1023}\)

Question 4.
How many pairs of testes are present in leech?
Answer:
There are 11 pairs of testes are present in Leech.

Question 5.
How is diastema formed in rabbit?
Answer:
Diastema is due to the absence of canine. It is a gap between incisors and premolars in the upper jaw and lower jaw.

Question 6.
What organs are attached to the two bronchi?
Answer:
The organs attached to the two bronchi are lungs.

Question 7.
Which organ acts as a suction pump in leech?
Answer:
The Pharynx acts as a suction pump in Leech.

Question 8.
What does CNS stand for?
Answer:
The full form of CNS is Central Nervous System.

Question 9.
Why is the teeth of rabbit called heterodont?
Answer:
The dentition of rabbit is called heterodont, as they have different types of teeth (Incisors, premolars and molars).

Question 10.
How does leech suck blood from the host?
Answer:
The Anterior sucker helps in feeding, while both the suckers, help in attachment and locomotion.

VI. Short answer questions:

Question 1.
Why are the rings of cartilages found in trachea of rabbit?
Answer:
The wall of larynx which serves as the voice box is supported by 4 cartilaginous plates. When the air passes the vocal cord, it vibrates resulting in sound production.

Question 2.
List out the parasitic adaptations in the leech.
Answer:
Leeches lead a parasitic mode of life, by sucking the blood of vertebrates. The adaptations are

• Blood is sucked by the pharynx.
• Anterior and Posterior Suckers are provided, by which the animal attaches itself to the body of the host.
• The three Jaws, inside the mouth, causes a painless Y – shaped wound in the skin of the host,
• The salivary glands produce Hirudin, which does not allow the blood to coagulate. So, the continuous supply of blood is maintained.
• Parapodia and Setae are absent.
• Blood is stored in the crop. It gives nourishment to the leech for several months. So there is no elaborate secretion of the digestive juices and enzymes.

VII. Long answer questions:

Question 1.
How is the circulatory system designed in leech to compensate the heart structure?
Answer:
The circulation in Leech is Haemocoelic system. There are no true blood vessels. The blood vessels are replaced by channels called Haemocoelic channels or canals, filled with blood like a fluid. The coelomic fluid contains Haemoglobin.

There are four longitudinal channels. One channel lies above (dorsal) to the Alimentary canal, one below (ventral) to the Alimentary canal. The other two channels lie on either (lateral) side of the Alimentary canal, which serves as a heart and have inner valves. All the four channels are connected together posteriorly in the 26th segment. Thus the circulatory system is designed in Leech to compensate the heart structure.

Question 2.
How does locomotion take place in leech?
Answer:

1. Looping or Crawling movement : Looping movement is brought about by the contraction and relaxation of muscles. The two suckers serve for attachment during movement. The animal fixes its posterior sucker on the substratum.
2. Swimming movement : The animal swims in the water by undulating movements of the body.

Question 3.
Explain the male reproductive system of rabbit with a labelled diagram.
Answer:
The male rabbit has a pair of testes. They are oval in shape. They are kept in two sacs called scrotal sacs hanging down from the abdomen. Each testes is formed of numerous fine tubules called seminiferous tubules. A coiled tubule called epididymis is formed at the end of seminiferous tubules. Epididymis lead into the sperm duct called vas deferens. The vas deferens run forward and enters abdominal cavity through urinary bladder. The urethra runs back and passes into the penis. There are three accessory glands associated with the male reproductive system. They are prostate glands, cowper’s gland and perineal glands. Their secretion nourishes and activates the reproduction.

VIII. Higher Order Thinking Skills (HOTS).

Question 1.
Arjun is studying in the tenth standard. He was down with fever and went to meet the doctor. As he went to the clinic he saw a patient undergoing treatment for severe leech bite. Being curious, Arjun asked the doctor why leech bite was not felt as soon as it attaches to the skin? What would have been the reply given by the doctor?
Answer:
The doctors would have replied that the leeches inject an anaesthetic substance, that prevents the host from feeling their bite.

Question 2.
Shylesh has some pet animals at his home. He has few rabbits too, one day while feeding them he observed something different with the teeth. He asked his grandfather, why is it so? What would have been the explanation of his grandfather?
Answer:
The rabbit has three types of teeth – Incisors are front teeth used for cutting, premolar and molar are used for grinding. Canine is absent as rabbit are herbivores. The gap between the incisor and premolar is called diastema. It helps in mastication and chewing of food in herbivores animal.

IX. Value-Based Questions:

Question 1.
Leeches do not have an elaborate secretion of digestive juices and enzymes. Why?
Answer:
The digestion in leeches in very slow. So, the blood stored in the crop gives nourishment to the leech for several months. So there is not elaborate secretion of digestive juices and enzymes.

Question 2.
How is the digestive system of rabbit suited for herbivorous mode of feeding?
Answer:
Rabbit are herbivores which feed on plants. The plant contain cellulose which need cellulose to digest. The laccum of Rabbit contain large number of symbiotic bacteria that helps in digestion of cellulose.

Samacheer Kalvi 10th Science Structural Organisation of Animals Additional Important Questions and Answers

I. Choose the correct answer:

Question 1.
(a) Vas deferens and Epididymis
(b) Ovary and Caeca
(c) Hirudin and Stomach
(d) Nephridia and Papillae.
Answer:
(a) Vas deferens and Epididymis

Question 2.
Diastema is:
(a) A part of pelvic girdle in rabbit
(b) A type of tooth in rabbit
(c) Space in teeth line in mammals
(d) Structure in eye of rabbit
Answer:
(c) Space in teeth line in mammals

Question 3.
(a) Suckers and Mammary glands
(b) Cowper’s gland and Perineal gland
(c) Forebrain and Oesophagus
(d) Cellulose and Colouration.
Answer:
(b) Cowper’s gland and Perineal gland

Question 4.
If the dental formula of rabbit is \(\frac{2023}{1023}\) What does it show?
(a) Total number of teeth in Rabbit is 15
(b) Number of total incisors in Rabbit is 3
(c) Diastema is present between incisors and premolars
(d) In the formula 2033 is for adult and 1023 is for young ones
Answer:
(c) Diastema is present between incisors and premolars

Question 5.
Number of pairs of salivary glands present in Rabbit is:
(a) one
(b) three
(c) four
(d) five
Answer:
(c) four

Question 6.
Number of Vertebrae in rabbit is:
(a) 44 – 47
(b) 40 – 44
(c) 42 – 48
(d) 47 – 50
Answer:
(a) 44 – 47

Question 7.
If the diaphragm of a rabbit is perforated breathing is:
(a) Not affected
(b) Increased
(c) Decreased
(d) Stopped
Answer:
(d) Stopped

Question 8.
Tracheal rings in rabbit are:
(a) complete
(b) dorsally incomplete
(c) lateral incomplete
(d) incomplete
Answer:
(b) dorsally incomplete

Question 9.
Which one of the following is not a characteristic of leech?
(a) closed circulatory system
(b) segmentation
(c) pseudo coelom
(d) ventral nerve cord
Answer:
(c) pseudo coelom

Question 10.
The blood vascular system, of rabbit is:
(a) open type
(b) closed type
(c) semi closed type
(d) semi open type
Answer:
(b) closed type

Question 11.
The wall of Rabbit’s heart is thick due to the presence of:
(a) Inner layer endocardium
(b) Middle layer myocardium
(c) Outer layer pericardium
(d) Outer layer epicardium
Answer:
(b) Middle layer myocardium

Question 12.
Leech belongs to the class:
(a) polychaeta
(b) oligochaeta
(c) hirundinea
(d) archiannelida
Answer:
(c) hirundinea

Question 13.
A temporary clitellum occur during the breeding season in:
(a) Pheretima
(b) Heteroneris
(c) Hirundinaria
(d) Aphrodile
Answer:
(c) Hirundinaria

Question 14.
Saliva of leeches contains an anti coagulation called:
(a) Heparin
(b) Histamine
(c) Hirudin
(d) Haematin
Answer:
(c) Hirudin

II. Fill in the blanks:

1. Hirudinaria granulosa belong to the phylum ……..
2. The scientific name of the rabbit is ………
3. ………. is the segmentation of the body.
4. The type of movement is brought by the contraction and relaxation of muscles in leeches is ………
5. In leech, the digestion takes place in stomach by the action of …………
6. The ……….. prevents the entry of food into the trachea through the glottis.
7. The existence of two sets of teeth in the life of an animal is called ………… dentition.
8. ……….. contains bacteria that helps in digestion of cellulose.
9. The anterior part of the oviduct in rabbit is …………
10. Breathing movement in mammals are brought by ………..
Answer:
1. Annelida
2. Oryctolagus cuniculus
3. Metamerism
4. Looping or crawling movement
5. Proteolytic enzyme
6. Epiglottis
7. Diphyodont
8. Caecum
9. Fallopian tube
10. Diaphragm

III. Identify whether the statements are True or False. Correct the false statement:

1. Mammary gland in male is the most striking feature of mammals.
2. The leech makes a triradiate or y-shaped incision in the skin of the host by the joins protrude through the mouth.
3. Crop and its diverticular in leech can store large amount of blood which can be slowly digested.
4. Breathing movement in Rabbit are brought by the movement of vibrissae.
5. In rabbit pair of cowper’s gland and perineal gland are present only in the male.

Answer:

1. False – Mammary gland in female is the most striking feature of mammals.
2. True
3. True
4. False – Breathing movement in Rabbit are brought by Diaphragm
5. False – In rabbit pair of cowper’s gland and perineal gland are present both male and female

IV. Match the following:

Answer:
A. (v)
B. (i)
C. (ii)
D. (iii)
E. (iv)

V. Answer in a sentence:

Question 1.
Name the excretory organ of leech.
Answer:
Excretion in leech takes place by nephridia.

Question 2.
Give the Scientific name of Rabbit.
Answer:
Oryctolagus Cuniculus.

Question 3.
Where is the brain of rabbit located?
Answer:
The brain of rabbit is located in the cranial cavity and covered by three membrane of duramater, piamater and arachnoid membrane.

Question 4.
How many pairs of cranial nerves are there in the Peripheral Nervous System?
Answer:
12 pairs of cranial nerves.

Question 5.
What is other name of whiskers in rabbit?
Answer:
The sides of the upper lip produce stiff long thick hairs called vibrissae or whisker which are tactile sensory organ.

Question 6.
Which type of rabbit are endangered species?
Answer:
Pygmy Rabbits are listed as an endangered species.

Question 7.
Name the existence of two sets of teeth in the life of an animal.
Answer:
Diphyodont dentition

Question 8.
Why Rabbits are called gregarious animals?
Answer:
Rabbits are called gregarious animals as they move in group.

Question 9.
Which animals are called sanguivorous?
Answer:
Blood sucking animals.

Question 10.
What are nephridropores?
Answer:
In leech, excretion takes place by segmentally arranged paired tubules called nephridia. There are 17 pairs of nephridia which open by nephridiopores from 6th to 22nd segment.

VI. Short Answer Questions:

Question 1.
Write the systematic position of Indian Cattle Leech.
Answer:

Question 2.
What do you know about the Trunk of Rabbit?
Answer:
The trunk is divisible into an anterior thorax and a posterior abdomen. In females, four or five teats or nipples are present on the ventral surface between Thorax and abdomen. The trunk has two pairs of Pentadactyl limbs. The forelimbs are shorter than the hind limbs.

All the digits bear claws. The anus is present at the posterior end. In females, on the ventral side, a slit-like Vulva is present. In males, the Penis is present in the ventral side of Anus. The male has a pair of testes, enclosed by Scrotal Sacs.

Question 3.
How do the leeches respire?
Answer:
There is no special respiration organ in leech. The skin serves as a respiratory i organ. The capillaries containing the haemocoelomic fluid extend in between the cells of the epidermis, acts as a permeable membrane through which the exchange of gases takes place by diffusion.

Question 4.
What are diphyodont dentition and Heterodont dentition?
Answer:
The existence of two sets of teeth in the life of an animal is called diphyodont dentition. The two types of teeth are Milk teeth (Young ones) and Permanent teeth (in adults).

The different types of dentition are called Heterodont. There are four kinds of teeth in mammals.
The incisors (I), Canines (C), Premolars (PM) and Molars (M).

Question 5.
List out the five layers of body wall of Leech.
Answer:
The body wall of leech consists of five layers.

1. Cuticle
2. Epidermis
3. Dermis
4. Muscular layer and
5. Botryoidal tissue

Question 6.
Give the systematic position of Rabbit.
Answer:

Question 7.
Explain the Respiratory system of Leech.
Answer:
Respiration takes place through the skin in Leech. Dense, network to tiny blood vessels called Capillaries, containing haemocoel fluid extend, in between the cells of the epidermis. The exchange of respiratory gases takes place by diffusion. Oxygen dissolved in water diffuses through the skin, into haemocoel fluid, while Carbon dioxide, diffuses out. The skin is kept moist and slimy, due to the secretion of mucus, which prevents the skin from drying.

Question 8.
List out the steps involved in Inspiration in Rabbit.
Answer:
During Inspiration the atmospheric air takes the following route.

VII. Long answer questions:

Question 1.
Compare the digestive system of Leech and Rabbit.
Answer:

Question 2.
Short notes on the Nervous System of Leech.
Answer:
The Central Nervous System of Leech consists of a nerve ring and a paired ventral nerve cord. The nerve ring surrounds the Pharynx and is formed of Suprapharyngeal ganglion (brain), Circum pharyngeal connective and Subpharyngeal ganglion. The Subpharyngeal ganglion lies below the Pharynx and is formed by the fusion of four pairs of Ganglia.

Students can download 10th Science Chapter 12 Plant Anatomy and Plant Physiology Questions and Answers, Notes, Samacheer Kalvi 10th Science Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

Tamilnadu Samacheer Kalvi 10th Science Solutions Chapter 12 Plant Anatomy and Plant Physiology

Samacheer Kalvi 10th Science Plant Anatomy and Plant Physiology Text Book Back Questions and Answers

I. Choose the correct answer:

Question 1.
Casparian strips are present in of the root.
(a) cortex
(b) pith
(c) pericycle
(d) endodermis
Answer:
(d) endodermis

Question 2.
The endarch condition is the characteristic feature of ______.
(a) root
(b) stem
(c) leaves
(d) flower.
Answer:
(b) stem

Question 3.
The xylem and phloem arranged side by side on same radius is called:
(a) radial
(b) amphivasal
(c) conjoint
(d) None of these
Answer:
(c) conjoint

Question 4.
Which is formed during anaerobic respiration:
(a) Carbohydrate
(b) Ethyl alcohol
(c) Acetyl CoA
(d) Pyruvate
Answer:
(b) Ethyl alcohol

Question 5.
Kreb’s cycle takes place in ______.
(a) chloroplast
(b) mitochondrial matrix
(с) stomata
(d) inner mitochondrial membrane.
Answer:
(b) mitochondrial matrix

Question 6.
Oxygen is produced at what point during photosynthesis?
(a) when ATP is converted to ADP
(b) when CO₂ is fixed
(c) when H₂O is splitted
(d) All of these
Answer:
(d) All of these

II. Fill in the blanks:

1. Cortex lies between ……….
2. Xylem and phloem occur on the same radius constitute a vascular bundle called ………..
3. Glycolysis takes place in ………..
4. The source of O₂ liberated in photosynthesis is ……….
5. …….. is the ATP factory of the cells.

Answer:

1. epidermis and Pericycle
2. conjoint bundles
3. cytoplasm
4. splitting of Water molecules
5. Mitochondria

III. State whether the statements are true or false. Correct the false statement.

1. Phloem tissue is involved in the transport of water in plants.
2. The waxy protective covering of a plant is called as the cuticle.
3. In monocot, stem cambium is present in between xylem and phloem.
4. Palisade parenchyma cells occur below the upper epidermis in the dicot root.
5. Mesophyll contains chlorophyll.
6. Anaerobic respiration produces more ATP than aerobic respiration.

Answer:

1. False – Phloem tissue is involved in the transport of food in plants.
2. True
3. False – In monocot stem cambium is absent.
4. True
5. True
6. False – Aerobic respiration produces more ATP than anaerobic respiration.

IV. Match the following:

Answer:
A. (iii)
B. (iv)
C. (i)
D. (v)
E. (ii)

V. Answer in a sentence:

Question 1.
What is the collateral vascular bundle?
Answer:
If xylem and phloem in a vascular bundle are arranged along the same radius with phloem towards the outside, such vascular bundle is called a collateral vascular bundle.

Question 2.
Where does the carbon that is used in photosynthesis come from?
Answer:
The carbon that is used in photosynthesis comes from CO₂ from the air.

Question 3.
What is the common step in aerobic and anaerobic pathway?
Answer:
Glycolysis is the common step in aerobic and anaerobic respiration.

Question 4.
Name the phenomenon by which carbohydrates are oxidized to release ethyl alcohol.
Answer:
Alcohol fermentation.

VI. Short answer questions:

Question 1.
Give an account on vascular bundle of dicot stem.
Answer:
Vascular bundles of dicot stem are conjoint (xylem and phloem lies in the same radius) collateral (xylem is the centre and phloem lies towards periphery) endarch (proto xylem in the centre, Meta xylem lies in the periphery) and open (cambium present in between xylem and phloem: They are arranged in the form of ring around the pith.

Question 2.
Write a short note on mesophyll.
Answer:
In Dicot leaf, the tissue present between the upper and lower epidermis is called mesophyll. It is differentiated into

1. Palisade Parenchyma: They are found below the epidermis and are elongated. They have a number of chloroplasts and can take part in photosynthesis. The cells do not have intercellular spaces.
2. Spongy Parenchyma: They are found below the palisade parenchyma tissue. Cells are spherical or oval and are irregularly arranged. Cells have intercellular spaces and help in gaseous exchange.

In monocot leaves, mesophyll is present between both upper and lower epidermal layer. The cells are irregularly arranged with intercellular spaces. Mesophyll cells contain chloroplasts, to take part in photosynthesis.

Question 3.
Draw and label the structure of oxysomes.
Answer:

Question 4.
Name the three basic – tissues systems in flowering plants.
Answer:
The three basic tissue system in flowering plants are:

• Dermal or epidermal tissue system.
• Ground tissue system.
• Vascular tissue system.

Question 5.
What is photosynthesis and where in a cell does it occur?
Answer:
Photosynthesis is a process by which autotrophic organisms (green plants, algae and chlorophyll containing bacteria) utilize the energy from sunlight to synthesize their own food. It occur in the chloroplast of the cell.

Question 6.
What is respiratory quotient?
Answer:
Respiratory quotient is the ratio of volume of carbon dioxide liberated and the volume of oxygen consumed during respiration. It is expressed as

Question 7.
Why should the light – dependent reaction occur before the light-independent reaction?
Answer:
In light – dependent photosynthesis, the photosynthetic pigment absorbs the light energy and convert it into chemical energy, ATP and NADPH₂. These products move out from grana to the stroma of the chloroplast for the light-independent reactions (Dark reaction or Biosynthetic pathway). During this reaction, CO₂ is reduced in the carbohydrates with the help of light generated ATP and NADPH₂. So the light-dependent reaction should occur before the light-independent reaction.

Question 8.
Write the reaction for photosynthesis.
Answer:
The overall reaction for photosynthesis.

VII. Long Answer Questions:

Question 1.
Differentiate the following:
(a) Monocot root and Dicot root
Answer:

(b) Aerobic and Anaerobic respiration
Answer:

Question 2.
Describe and name three stages of cellular respiration that aerobic organisms use to obtain energy from glucose.
Answer:
The name and the three stages of cellular respiration.

• Glycolysis: (Glucose splitting): Glycolysis is the break down of one molecule of Glucose (6 Carbon) into two molecules of Pyruvic acid (3 Carbon). It takes place in the cytoplasm of the cell.
• Kreb’s cycle: This cycle occurs in the mitochondria matrix. At the end of Glycolysis, 2 molecules of pyruvic acid enter into mitochondria. The oxidation of pyruvic acid into CO₂ and H₂O takes place through this cycle. It is also called as Tricarboxylic Acid Cycle. (TCA)
• Electron transport chain: It is a system of Electron Transport Chain (ETC) located on the inner membrane of the mitochondria. NADH₂ and FADH₂ molecules formed during Glycolysis and Krebs cycle are oxidised to NAD+ and FAD+ to release the energy via electrons.

The electrons, as they move through the system, release energy which is trapped by ADP to synthesize ATP. This is called Oxidative Phosphorylation. During this process, oxygen which is the acceptor of electrons gets reduced to water.

Question 3.
How does the light dependent reaction differ from the light independent reaction?
What are the end product and reactants in each? Where does each reaction occur within the chioroplast?
Answer:

VIII. Higher Order Thinking Skills(HOTS):

Question 1.
The reactions of photosynthesis make up a biochemical pathway.
(a) What are the reactants and products for both light and dark reactions.
Answer:
The reaction of photosynthesis can be grouped into two: Light and Dark reaction.
The reaction involving pigments, solar energy and water that produce ATP and NADPH₂ are called light reaction.
The photosynthetic reactions in which CO₂ is reduced to carbohydrates making use of ATP and NADPH₂ generated by light reaction are called dark reaction.
The overall reaction of photosynthesis can be written as follows:

(b) Explain how the biochemical pathway of photosynthesis recycles many of its own reactions and identify the recycled reactants.
Answer:
Light reaction use light to synthesize ATP and NADPH₂. The calvin cycle uses these reactants to produce sugar from CO₂ molecule.
This cycle then produce NAP + ADP + Pi which is used in light reaction with H₂O molecules to produce ATP and NADPH₂ again.

Question 2.
Where do the light-dependent reaction and the Calvin cycle occur in the chloroplast?
Answer:
The Light-dependent reaction occurs in the Thylakoid membranes (Grana) of the chloroplast. The Light independent reaction occurs in the stroma of the chloroplast.

Samacheer Kalvi 10th Science Plant Anatomy and Plant Physiology Additional Important Questions and Answers

I. Choose the correct answer:

Question 1.
The root hairs originate from:
(a) trichoblast
(b) endodermis
(c) hypodermis
(d) pericycle
Answer:
(a) trichoblast

Question 2.
Sachs classified tissue system in plants into _____.
(a) five types
(b) two types
(c) three types
(d) four types.
Answer:
(c) three types

Question 3.
The innermost layer of the cortex is:
(a) epidermis
(b) hypodermis
(c) endodermis
(d) pericycle
Answer:
(c) endodermis

Question 4.
The powerhouse of the cell or ATP factory of the cells _____.
(a) Plastids
(b) Vacuoles
(c) Nucleus
(d) Mitochondria.
Answer:
(d) Mitochondria.

Question 5.
The vascular bundle with protoxylem facing centre of the stem is:
(a) exarch
(b) endarch
(c) tetrarch
(d) polyarch
Answer:
(b) endarch

Question 6.
This is the first step of both Aerobic and Anaerobic respiration _____.
(a) Electron transport chain
(b) Respiratory Quotient
(c) Glycolysis
(d) Kreb’s Cycle.
Answer:
(c) Glycolysis

Question 7.
The vascular bundle in the leaf is:
(a) collateral and open
(b) collateral and closed
(c) bicollateral and open
(d) collateral and exarch
Answer:
(b) collateral and closed

Question 8.
Photosynthesis takes place in:
(a) mitochondria
(b) peroxisomes
(c) chloroplast
(d) ribosomes
Answer:
(c) chloroplast

Question 9.
The dark reaction of photosynthesis were discovered by:
(a) Embden and Meyer
(b) Melvin and Calvin
(c) Kreb
(d) Pamas
Answer:
(b) Melvin and Calvin

Question 10.
………. is the organelle of cell respiration.
(a) mitochondria
(b) chloroplast
(c) plastids
(d) cell wall
Answer:
(a) mitochondria

Question 11.
The hypodermis of monocot stem consists of:
(a) Collenchyma
(b) Sclsrenchyma
(c) Angular collenchyma
(d) Parenchyma
Answer:
(b) Sclsrenchyma

Question 12.
The layer is morphologically homologous to the endodermis found in the root which is:.
(a) periderm
(b) epidermis
(c) starch sheath
(d) mesophyll tissue
Answer:
(c) starch sheath

Question 13.
Pericycle is absent in:
(a) dicot stem
(b) monocot root
(c) dicot root
(d) monocot stem
Answer:
(d) monocot stem

Question 14.
………. is not a characteristic feature of spongy parenchyma.
(a) Gaseous exchange
(b) Photosynthesis
(c) Irregular
(d) Closely arranged
Answer:
(d) Closely arranged

Question 15.
Which of the following is not applicable of dicot stem?
(a) wedge shaped
(b) endarch
(c) collateral
(d) closed
Answer:
(d) Closely arranged

II. Application based question:

Question 1.
In the given flow chart different layer of monocot root is shown. What is A and B?

(a) A – Hypodermis, B – Vascular bundle
(b) A – Cortex, B – Vascular bundle
(c) A – Cortex, B – Xylem
(d) A – Hypodermis, B – Xylem
Answer:
(b) A – Cortex, B – Vascular bundle

Question 2.
Casparian strip are characteristic feature of A endodermis and it is made up of B. What is A and B respectively?
(a) shoot, suberin
(b) root, lignin
(c) root, suberin
(d) root and shoot, suberin
Answer:
(c) root, suberin

Question 3.
Which of the following is present in monocot leaves?
A. Bulliform cell
B. Leaf base
C. Bundle sheath
D. Resin gland
E. Water cavity
(a) A, B, C, E
(b) A, B, D, E
(c) A, B, E
(d) A, B, C
Answer:
(d) A, B, C

Question 4.
A vascular bundle in which phloem is on both the sides of the xylem and separated from it by strips of cambium is said to be:
(a) Collateral open
(b) Bicollateral open
(c) Concentric
(d) Bicollateral closed
Answer:
(b) Bicollateral open

Question 5.
Presence of cuticle is a common character of:
A. Monocot stem
B. Dicot stem
C. Monocot root
D. Dicot root
E. Monocot leaf
F. Dicot leaf
(a) A, B, E, F
(b) B, F
(c) A, B, C, D, E, F
(d) A, E, F
Answer:
(a) A, B, E, F

III. Fill in the blanks:

1. ………. is known as “Father of Plant Anatomy”.
2. ……….. are the group of cells that are similar or dissimilar in structure and origin, but perform similar function.
3. Based on the ability to divide, tissues are classified into ……….. and ……… tissue.
4. ………. is the outermost layer.
5. The main function of vascular tissue system are transport of ……….. and ……….
6. Epidermis protects the ……… tissue.
7. ………, ………., ………… and ……….. forms the ground tissue system.
8. Epiblema is also known as ……… or ……….
9. ……….. helps in the movement of water and dissolved salts from cortex into xylem.
10. The tissue present between xylem and phloem is called …………
11. All the tissues inner to endodermis constitute …………
12. The tissue present between the upper and lower epidermis is called …………
13. Reaction centres and the accessory pigments together are called …………
14. Light reaction takes place in ………. membrane of the chloroplast.
15. Kreb cycle is also known as ……….
16. Glycolysis take place in ……… of the cell.
17. Krebs cycle occurs in ……….. matrix.
18. The gas evolved during photosynthesis is ……….
19. The first step in aerobic respiration is ………..
20. Energy currency of cells is ………..
21. Major functions of epiblema is ……….
Answer:
1. Nehemiah Grew
2. Tissues
3. Meristamatic and Permanent
4. Epidermis
5. Water and Food
6. inner
7. Cortex, Endodermis, Pericycle and Pith
8. Rhizodermis or Piliferous layer
9. Casparian strips
10. Conjuctive tissue
11. Stele
12. Hypodermis
13. Photosystems
14. thylakoid
15. Tricarboxylic Acid Cycle (TCA)
16. Cytoplasm
17. Mitochondria
18. Oxygen
19. Glycolysis
20. ATP
21. Protection

IV. Match the following:

Answer:
A. (iv)
B. (iii)
C. (i)
D. (v)
E. (ii)

V. Answer in Sentence:

Question 1.
What are the functions of Epidermis?
Answer:

• The epidermis protects the inner surface.
• Stomata help in transpiration.
• Root hairs help in absorption of water and minerals.

Question 2.
Name the factors which affect photosynthesis.
Answer:
The process of photosynthesis is affected internally by:

1. Pigments
2. Leaf age
3. Accumulation of carbohydrates and
4. Hormones.

The process of photosynthesis is affected externally by:

1. Light
2. CO₂
3. Temperature
4. Water
5. Minerals.

Question 3.
What are Oxysomes?
Answer:
The inner mitochondria membrane bear minute regularly spaced, Tennis racket shaped particles called Oxysomes, which involve in ATP synthesis.

Question 4.
What is Cortex?
Answer:
The region below the epidermis is called cortex. Its main function is to store starch.

Question 5.
What is Pericycle?
Answer:
Pericycle is the outer most layer of stele. It is made of single layer of thin walled cells.

Question 6.
What are the functions of chloroplasts?
Answer:

• Photosynthesis
• Storage of starch
• Synthesis of fatty acids
• Storage of lipids
• Formation of chloroplasts.

Question 7.
Where are passage cell located and write its function?
Answer:
The passage cell is an endodermal cell located opposite to the protoxylem, which are thin wall without casparian strips. The main function of passage cell is entry of water from cortex to xylem.

Question 8.
What is protoxylem lacuna?
Answer:
In mature vascular bundle the lowest proto xylem disintegrates and form a cavity called protoxylem lacuna. Eg: Monocot stem.

Question 9.
Define Kreb’s cycle.
Answer:
The series of cyclic reaction involved in converting pyruvic acid to CO₂ and water in mitochondria is called Kreb’s cycle.

Question 10.
Why mitochondria is called ‘Power house of the cell’?
Answer:
A large number of ATP molecules are produced in the mitochondria, so they are called power house of the cell.

VI. Short answer questions:

Question 1.
Name the three types of plastids.
Answer:

1. Chloroplast: green coloured plastids helps in photosynthesis.
2. Chromoplast: yellow, red, orange coloured plastids, gives colour to flowers and fruits.
3. Leucoplast: colourless plastids, store food.

Question 2.
List out the functions of chloroplast.
Answer:

1. Photosynthesis
2. Storage of starch
3. Synthesis of fatty acids
4. Storage of lipids

Question 3.
What are Concentric bundles? Explain its types.
Answer:
Vascular bundles in which either xylem completely surrounds the phloem or phloem surrounds the xylem is called concentric vascular bundle. It is of two types:

1. Amphivasal: Xylem surrounds phloem. Eg: Dracaena
2. Amphicribral: Phloem surrounds xylem. Eg: Ferns

Question 4.
What are photosynthetic pigment?
Answer:

1. Pigments involved in photosynthesis are called Photosynthetic pigments.
2.  Primary pigment traps solar energy and converts it into electrical and chemical energy. Accessory pigments pass on the absorbed energy to primary pigment.

Question 5.
(a) Differentiate between Palisade parenchyma and spongy parenchyma.
Answer:

(b) Differentiate between Monocot ieaf and Dicot leaf.
Answer:

Question 6.
Define stele.
Answer:
Central Part inner to endodermis is called stele. It includes pericycle and vascular system.

Question 7.
Where respiratory cavity is located?
Answer:
The air space that is found next to the stomata is called respiratory cavity or sub stomatal cavity.

Question 8.
What is an isobilateral leaf? Give an example.
Answer:
In monocot leaf, the mesophyll is not differentiated into palisade parenchyma and spongy parenchyma (i.e., made of only spongy or palisade parenchyma) is called isobilateral leaf.
Eg: Grass (Monocot leaf)

Question 9.
What is dorsiventral leaf? Give an example.
Answer:
In dicot leaf, the mesophyll is differentiated into palisade parenchyma on the upper side and spongy parenchyma on the lower side. A leaf showing this differentiation is mesophyll is designated as dorsiventral. Eg: Dicot leaf.

Question 10.
Define tetrarch xylem.
Answer:
If the number of proto xylem points are four, the xylem is called tetrarch. Eg: Dicot root

Question 11.
What are generally called as accessory pigments?
Answer:
Photosynthetic pigments other than chlorophyll ‘a’ are generally I called accessory pigments. Eg: Chlorophyll ‘A’- Carotenoids and Xanthophyll.

Question 12.
W’rite any three significance of photosynthesis.
Answer:

1. It is the source of all our food and fuel,
2. It drives all other process of biological and a biological world,
3. It is responsible for the growth and sustenance of our biosphere.

Question 13.
What are the functions of epidermal tissue system?
Answer:

1. Epidermis protects the inner tissues.
2. Stomata helps in transpiration.
3. Root hairs help in absorption of water and minerals.

Question 14.
Differentiate between monocot and dicot stem.
Answer:

VII. Long answer questions:

Question 1.
Explain Epidermal tissue system.
Answer:

1. The outer most covering layer of plants.
2. It contains epidermis, stomata and epidermal out growths.
3. Epidermis are interrupted by many minute pores called stomata.
4. Epidermis is covered by cuticle to check evaporation of water.
5. Trichomes and root hairs are some epidermal growths.

Question 2.
Explain the types of Vascular bundle.
Answer:
Xylem and Phloem are present in the form of bundles called vascular bundles.
1. Radial
2. Conjoint
3. Concentric.
1. Radial vascular bundle : Xylem and phloem are arranged in an alternate matter or different radii are called Radial vascular bundle. Eg: roots

2. Conjoint vascular bundle : Xylem and phloem are arranged in the same radius are called conjoint vascular bundle. Divided in two types:
(a) Collateral vascular bundles : Xylem and phloem are arranged in the same radius with phloem towards the outside is called collateral vascular bundles. Eg: stem and leaf.
Collateral vascular bundles are of two types:

• Open collateral vascular bundle: Vascular bundle consists of cambial tissue in between xylem and phloem are called Open collateral vascular bundle. Eg: Dicot stem
• Closed collateral vascular bundle: Cambium is absent in vascular bundle are called Closed collateral vascular bundle. Eg: Monocot stem.

(b) Bicollateral : Phloem occurs on both the outer and inner side of xylem. This vascular bundle is Bicollateral vascular bundle. Eg: Cucurbita.

3. Concentric vascular bundle : The vascular bundle in which either phloem surrounds the xylem or xylem surrounds the phloem completely called Concentric vascular bundles. It is of two types: (a) Amphivasal, (b) Amphicribral.
(a) Amphivasal: The Xylem completely surrounds the phloem. Eg: Dracaena
(b) Amphicribral: The Phloem completely surrounds the xylem. Eg: Ferns

Exarch: Protoxylem vessels are present towards the periphery and meta xylem towards the centre. Eg: Root
Endarch: Protoxylem are present towards the centre and meta xylem towards the periphery. Eg: Stem

Question 3.
Explain the Primary structure of Monocot root.
Answer:
The internal structure of Monocot root has
1. Epiblema/Rhizodermis
2. Cortex
3. Endodermis
4. Stele
1. Epiblema/Rhizodermis:

• Outer most layer of monocot root.
• Made up of single layer of thin walled, paranchymatous cell.
• Root hair helps in absorption of water and minerals.
• Stomata and cuticle are absent.
• Main function is to protect inner tissue.

2. Cortex:

• The region below the epidermis is cortex.
• Made up of only parenchymatous cells with intercellular space.
• It is a multi layer.
• Function is to store water and food material.

3. Endodermis:

• Inner most cortex is called Endodermis.
• It forms a complete ring around the stele with characteristic Casparian strips and Passage cell.
• There is a band like thickening made of suberin in casparian strips.

(iv) Stele:
Central part inner to endodermis is stele.
It contains Pericycle, vascular bundles and pith.
(a) Pericycle:

• Outer most layer of stele made of single layer of tightly arranged Parenchymatous cell.
• Function is to originate lateral root.

(b) Vascular bundles:

• Radial arrangement of vascular tissue.
• Xylem is exarch and polyarch.
• The conjuctive tissue is sclerenchymatous tissue.

(c) Pith:

• Large central part, composed of parenchyma cells with intercellular spaces.
• Function is to store the starch.

Question 4.
Draw the structure of Dicot root.
Answer:

Question 5.
Describe the Primary structure of T.S of Monocot stem.
Answer:
(i) Epidermis:

• Outer most layer of monocot stem.
• Made up of single layer and tightly packed parenchyma cells.
• Outer wall is covered by thick cuticle.
• Few stomata are seen in epidermis.
• Multicellular hairs are absent.

(ii) Hvpodermis:

• The layer below the epidermis is called hypodermis.
• Hypodermis is made up of sclerenchymatous cells.
• It is interrupted by chlorenchyma.

Sclerenchyma provides mechanical support to plant.

(iii) Ground tissue:

• There is no distinction of cortex, endodermis, pericycle and pith.
• Inner to hypodermis parenchyma cell forms the ground tissue.

(iv) Vascular bundles:

• Vascular bundles are scattered in the ground tissue. Each vascular bundle are surrounded by bundle sheath by sclerenchymatous tissue.
• Vascular bundles are conjoint, collateral, endarch and closed.
• Xylem contains meta xylem and protoxylem.
• In mature Vascular bundle the lowest protoxylem disintegrates and form a cavity called protoxylem lacuna.
• Phloem contains seive tubes and companion cells.

(v) Pith:

• It is not differentiated in monocot stem.

Question 6.
Write a short note on structure of chloroplast.
Answer:
(i) Chloroplast are the actual site of photosynthesis.
(ii) They are green plastids containing green pigment called chlorophyll.
(iii) It mainly consists of Envelope, Stroma, Thylakoids and Grana.

Envelope : Chloroplast has outer and inner envelope membranes which is seperated by intermembrane space.
Stroma : Matrix present inside to the membrane is called stroma. It contains DNA, 70 S ribosomes and other molecules required for protein synthesis.
Thylakoids : It’s membrane encloses thylakoid lumen. Thylakoids forms a stack of disc like structures called a grana (singular-granum).
Grana : Some of the thylakoids are arranged in the form of discs stacked one above the other. These stacks are termed as grana,they are interconnected to each other by membranous lamellae called Fret channels.

Question 7.
Explain the primary structure of T.S Dicot stem.
Answer:
The internal structure of Dicot stem has
(i) Epidermis :

• Outer most layer of dicot stem made up of tightly packed parenchyma cells.
• Outer wall is covered by thick cuticle which check transpiration.
• Few stomata and multicellular hairs are present in epidermal cells.

(ii) Cortex :
Cortex is differentiated into 3 zones:

• Hypodermis : The layer below the epidermis is called Hypodermis. It is made by few layers of collenchymatous cells which gives mechanical strength.
• Middle cortex : Inner to hypodermis is made up of few layer of chlorenchymatous tissue which helps in photosynthesis.
• Inner cortex : Inner cortex is made by parenchyma cells which stores food materials. The inner most layer of cortex is called endodermis. The cells are compactly arranged in barrel shaped cells that contain starch grains. So this layer also called starch sheath.

(iii) Stele :
Central part inner to endodermis is called stele. It contains pericycle, vascular bundle and pith.

• Pericycle : A few layer of sclerenchyma cells occurs in patches outside the phloem in each vascular bundle.
• Vascular bundle : Vascular bundle are conjoint collateral, endarch and open. They are arranged in the form of ring.
• Pith : Large central part, composed if parenchyma cells with intercellular spaces. Function is to store the food.

Question 8.
Describe the structure of T.S of dicot leaf.
Answer:
The T.S of dicot leaf contains
(i) Epidermis – Upper and Lower
(ii) Mesophyll
(iii) Vascular bundles

(i) Epidermis :
The leaf is dorsiventral it has upper and lower epidermis.

• Upper Epidermis : Made up of single layer of tightly packed parenchyma cells. Cuticle is thicker than the lower epidermis.
• Lower Epidermis : Made up of single layer of parenchymatous cells with thin cuticle. Stomata are more in Lower epidermis. Used for transpiration and gaseous exchange.

(ii) Mesophyll :
The region between upper and lower epidermis is called mesophyll. It is differentiated into palisade and spongy parenchyma.

• Palisade parenchyma: Present below the upper epidermis cells are elongated. Cells do not have intercellular spaces. More number of chloroplast present. Function is photosynthesis.
• Spongy parenchyma: Present above the lower epidermis. Cells are irregular shaped. Cells have intercellular spaces less number of chloroplast is present. Function is gaseous exchange.

(iii) Vascular bundles : Vascular bundles are conjoint, collateral and closed. Vascular bundles are surrounded by a compact layer of parenchymatous cells. These are called Bundle sheath. Xylem is present towards the upper epidermis. Phloem is present towards the lower epidermis.

VIII. Higher Order Thinking Skills (HOT).

Question 1.
The cells of endodermis show band like thickening on their radial and inner tangential walls called casparian strips. Why?
Answer:
It is to prevent the re-entry of water into the cortex once water entered the xylem tissue.

Question 2.
Do plants like Croton, with non – green leaves have chlorophyll and do they perform photosynthesis?
Answer:
The chlorophyll is present in Croton leaves, embedded along with other coloured pigments like carotenoids and anthocyanin. These coloured pigments assist or help the pigment chlorophyll in the process of photosynthesis.

Question 3.
How do we see beautiful colours in Autumn and enjoy the fall?
Answer:
Chlorophyll gives a green colour to plants. During winter, there is not enough light for photosynthesis. So they use food, which is stored in summer. As the green chlorophyll disappears or fades away, we begin to see yellow, orange and red colour. We cannot see them in summer, because they are covered by the green chlorophyll.

But in autumn or fall season glucose trapped in the leaves, after photosynthesis stops. Sunlight and cool nights of autumn cause the leaves to turn this glucose into a red colour.
It is the combination of all these things, that make the beautiful colours, we enjoy in the fall.

Students can download 10th Social Science Geography Chapter 4 Resources and Industries Questions and Answers, Notes, Samacheer Kalvi 10th Social Science Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

Tamilnadu Samacheer Kalvi 10th Social Science Solutions Geography Chapter 4 Resources and Industries

Samacheer Kalvi 10th Social Science Resources and Industries Text Book Back Questions and Answers

I. Choose the correct answer

Question 1.
Manganese is used in:
(a) Storage batteries
(b) Steel Making
(c) Copper smelting
(d) Petroleum Refining
Answer:
(b) Steel Making

Question 2.
The Anthracite coal has
(a) 80 to 95% Carbon
(b) Above 70% Carbon
(c) 60 to 7% Carbon
(d) Below 50% Carbon
Answer:
(a) 80 to 95% Carbon

Question 3.
The most important constituents of petroleum are hydrogen and:
(a) Oxygen
(b) Water
(c) Carbon
(d) Nitrogen
Answer:
(c) Carbon

Question 4.
The city which is called the Manchester of South India is
(a) Chennai
(b) Salem
(c) Madurai
(d) Coimbatore
Answer:
(d) Coimbatore

Question 5.
The first Jute mill of India was established at:
(a) Kolkata
(b) Mumbai
(c) Ahmedabad
(d) Baroda
Answer:
(a) Kolkata

Question 6.
The first Nuclear Power station was commissioned in
(a) Gujarat
(b) Rajasthan
(c) Maharashtra
(d) Tamil Nadu
Answer:
(c) Maharashtra

Question 7.
The most abundant source of energy is:
(a) Biomass
(b) Sun
(c) Coal
(d) Oil
Answer:
(b) Sun

Question 8.
The famous Sindri Fertilizer Plant is located in
(a) Jharkhand
(b) Bihar
(c) Rajasthan
(d) Assam
Answer:
(a) Jharkhand

Question 9.
The nucleus for the development of the chotanagpur plateau region is:
(a) Transport
(b) Mineral Deposits
(c) Large demand
(d) Power Availability
Answer:
(b) Mineral Deposits

Question 10.
One of the shore-based steel plants of India is located at
(a) Kolkata
(b) Tuticorin
(c) Goa
(d) Visakhapatnam
Answer:
(d) Visakhapatnam

II. Match the following

Question 1.
Match the Column I with Column II.

Answer:
A. (ii)
B. (i)
C. (iv)
D. (v)
E. (iii)

Question 2.
Match the Column I with Column II.

Answer:
A. (v)
B. (iv)
C. (i)
D. (ii)
E. (iii)

III. Answer the following questions briefly

Question 1.
Define the resource and state its types.
Answer:
Any matter or energy derived from the environment that is used by living things including humans is called a natural resource.
Types of Natural Resources are:

1. Renewable and
2. Non – renewable resources.

Question 2.
Name the states that lead in the production of Iron ore in India.
Answer:
Jharkhand is the leading producer of Iron ore (25%), other states are Odisha (21%), Chattisgarh (18%), Karnataka (20%), Andhra Pradesh (5%) and also the state of Tamil Nadu.

Question 3.
What are the minerals and its types?
Answer:
A mineral is a natural substance of organic or inorganic origin with definite chemical and physical properties.
Types of Minerals are:

1. Metallic minerals
2. Non – metallic minerals.

Question 4.
State the uses of Manganese.
Answer:

1. Manganese is a silvery grey element always available with iron, laterite and other minerals.
2. It is very hard and brittle. So it is used for making iron and steel to give strength.
3. It also serves as raw materials for alloying.
4. It is also used in the manufacture of bleaching powder, insecticides, paints and batteries.

Question 5.
What is natural gas?
Answer:
It usually accompanies petroleum accumulations.
[OR]
Natural gas is an important clean energy resources found in association with or without petroleum. It is used as a source of energy as well as an industrial raw material in the petrochemical industry. It is considered an eco-friendly fuel because of low carbondioxide emissions.

Question 6.
Name the different types of coal with their carbon content.
Answer:
Based on carbon content coal is classified into

1. Anthracite – contains 80% to 90% carbon.
2. Bituminous – contains 60% to 80% carbon.
3. Lignite – contains 40% to 60% carbon
4. Peat – less than 40% carbon

Question 7.
Mention the major areas of jute production in India.
Answer:
West Bengal, Andhra Pradesh, Bihar, Uttar Pradesh, Assam, Chattisgarh, Odisha are the major jute producing area.

Question 8.
Name the important oil producing regions of India.
Answer:
West coast: Mumbai high, Gujarat coast, Basseim, Aliabet (South of Bhavanagar), Ankleshwar, Cambay – Luni region, Ahmedabad -Kaloi region and Punjab – Haryana.

East Coast: Brahmaputra valley, Digboi, Nahoratitya, Moran-Hugrijan, Rudrasagar-Lawa (Assam region), Surrma Valley. Andaman and Nicobar, Gulf of Mannar, Punjab. Haryana, Baleshwar coast.

IV. Distinguish between

Question 1.
Renewable and non-renewable resources
Answer:
Renewable resources:

1. These resources can be replenished after utilization.
2. Abundantly available in nature.
3. Eg: Sun energy, Wind etc.

Non-Renewable resources:

1. These resources cannot be regained after utilization.
2. Limited stock take millions of years for formation.
3. Eg: Minerals

Question 2.
Metallic and non-metallic minerals
Answer:
Metallic minerals:

1. These minerals contain one or more metallic elements.
2. They can be further classified into ferrous and Non-ferrous minerals.
3. Eg: Iron-ore, Manganese

Non-Metallic minerals:

1. These minerals do not contain metal in them.
2. They can be classified into energy fuels and construction minerals.
3. Eg: Coal, Petroleum, lime stone, Gypsum.

Question 3.
Agra based industry and mineral based industry.
Answer:
Agro based industry:

1. These industries obtain raw materials from agricultural products.
2. Eg: Cotton textile industry, Jute mills, Silk industry, Sugar industry etc.
3. Labour intensive

Mineral based industry:

1. These industries obtain raw materials from metallic and non- metallic minerals.
2. Eg: Coal industry, Iron and Steel industry etc.
3. Capital intensive

Question 4.
Jute industry and sugar industry.
Answer:
Jute industry:

1. Second largest textile industry.
2. Jute fibre is the basic raw material.
3. Gunny bags, Canvas, pack sheets,Cordage are some of the Jute products.
4. Concentrated in and around West Bengal.

Sugar industry:

1. Second largest agro based industry.
2. Sugarcane is the basic raw material.
3. Sugar Jaggery, Khandsari are some of the products of sugar industry.
4. Uttar Pradesh have more than 50% of the sugar industries.

Question 5.
Conventional energy and non- conventional energy
Answer:
Conventional energy:

1. Non renewable energy.
2. Mainly energy is produced by burning fossil fuels.
3. Production of energy till the stock of mineral availability.
4. Thermal power – Coal, petroleum and Natural gas and Nuclear minerals.

Non-Conventional energy:

1. Renewable energy
2. Mainly energy is produced by harnessing power from nature.
3. Continuous flow of energy production is possible.
4. Solar energy, Wind energy. Bio mass energy, tidal and wave energy.

V. Answer the following in a paragraph

Question 1.
Write about the distribution of cotton textile industries in India.
Answer:
The cotton textile industries contribute about 7% of industrial output, 2% of India’s GDP and 15% of the country’s export earnings. It is one of the largest sources of employment generation in the country. At present there are 1,719 textile mills in the country. Out of which 188 mills are in public sector, 147 in cooperative sector and 1,284 in private sector. Currently, India is the third largest producer of cotton and has the largest loom arc and ring spindles in the world. At present, cotton textile industry is the largest organized modem industry of India. About 16% of the industrial capital, 14% of industrial production and over 20% of the industrial labour of the country are engaged in this industry.

The higher concentration of textile mills in and around Mumbai, makes it as “Manchester of India”. Presence of black cotton soil in Maharashtra, humid climate, presence of Mumbai port, availability of hydro power, good market and well developed transport facility favour the cotton textile industries in Mumbai. The major cotton textile industries are concentrated in the states of Maharashtra, Gujarat, West Bengal, Uttar Pradesh and Tamil nadu. Coimbatore is the most important centre in Tamil nadu with 200 mills out of its 435 and called as “Manchester ‘ of South India”. Erode, Tirupur, Karur, Chennai, Thirunelveli, Madurai, Thoothukudi, Salem and Virudhunagar are the other major cotton textiles centres in the state.

Question 2.
Explain the factors responsible for the concentration of jute industries in the Hoogly region.
Answer:
The following factors are responsible for the concentration of Jute industries in the Hoogly region in West Bengal.

1. Raw materials: West Bengal is the largest producer of Jute. Availability of raw Jute for production.
2. Processing: Jute require fresh water for processing. Abundant water supply is available by the riverines and continuous supply of fresh water is ensured due to Perennial nature.
3. Transport: Well connected by the network of water ways, road ways and railways.
4. Cheap labour: West Bengal is one of the densely populated area . So cheap labour is available.
5. Market: Kolkatta being one of the textile centre great demand for the product as well as port facilities available for export.

Question 3.
Write an account on the major iron and steel industries of India.
Answer:
Iron and Steel industry is the basic industry. The raw materials are obtained both from Metallic and Non-Metallic minerals.

Iron and Steel industries are located in close proximity to the coal fields or Iron ore mines.

VI. On the outline map of India mark the following.

Question 1.
iron ore production centres.
Answer:

Question 2.
Centres of Petroleum and Natural Gas production.
Answer:

Question 3.
Coal mining centres.
Answer:

Question 4.
Areas of cultivation of cotton.
Answer:

Question 5.
Iron and Steel industries.
Answer:

Samacheer Kalvi 10th Social Science Resources and Industries Additional Important Questions and Answers

I. Choose the correct answer

Question 1.
The ………………. is called as mineral oil.
(a) Petroleum
(b) Coal
(c) Natural gas
(d) Mica
Answer:
(a) Petroleum

Question 2.
Manchester of India is ……..
(a) Delhi
(b) Mumbai
(c) Chennai
Answer:
(b) Mumbai

Question 3.
The ………………. is the largest oil field in India producing 65% of oil.
(a) Ankaleshwar
(b) Mumbai high
(c) Kalol
(d) Surma valley
Answer:
(b) Mumbai high

Question 4.
Chotta Nagpur plateau is noted for ……..
(a) Natural vegetation
(b) Mineral resource
(c) Cotton cultivation
Answer:
(b) Mineral resource

Question 5.
TamilNadu produces about ………………. % of the total thermal electricity produced in India.
(a) 5
(b) 20
(c) 18
(d) 90
Answer:
(a) 5

Question 6.
In India most of the Iron and Steel industries are located in the …… plateau.
(a) Chott Nagpur
(b) Deccan
(c) Malwa
Answer:
(a) Chott Nagpur

Question 7.
Areas near ………………. district has the largest concentrations of wind farm capacity at a single location in the world.
(a) Ramanathapuram
(b) Tuticorin
(c) Thiruvallur
(d) Kanyakumari
Answer:
(d) Kanyakumari

Question 8.
The resources that can be reproduced again and again is called ……
(a) Mineral resources
(b) Renewable resource
(c) Natural resource
Answer:
(b) Renewable resource

Question 9.
Bysinosis is an occupational lung disease caused by exposure to:
(a) natural gas
(b) cotton dust
(c) coal power
(d) automobile
Answer:
(b) cotton dust

Question 10.
Lignite is extracted in Tamil Nadu …….
(a) Kadaloor
(b) Neyveli
(c) Madurai
Answer:
(b) Neyveli

Question 11.
National News Print and Papermills (NEPA) is in ………………. state.
(a) Odisha
(b) West Bengal
(c) TamilNadu
(d) Madhya Pradesh
Answer:
(d) Madhya Pradesh

Question 12.
Sugar bowl of India is …….
(a) West Bengal
(b) Uttar pradesh and Bihar
(c) Mumbai
Answer:
(b) Uttar pradesh and Bihar

Question 13.
The ………………. is the largest producer of electronic goods in India.
(a) Bengaluru
(b) Mysuru
(c) Delhi
(d) Jaipur
Answer:
(a) Bengaluru

Question 14.
The leading producer of electronic goods is ……..
(a) Bangalore
(b) Coimbatore
(c) Hyderabad
Answer:
(a) Bangalore

Question 15.
………………. is an aluminium ore.
(a) Manganese
(b) Magnesium
(c) Bauxite
(d) Anthracite
Answer:
(c) Bauxite

II. Match the following

Question 1.
Match the Column I with Column II.

Answer:
A. (iv)
B. (iii)
C. (i)
D. (v)
E. (ii)

Question 2.
Match the Column I with Column II.

Answer:
A. (iii)
B. (v)
C. (ii)
D. (i)
E. (iv)

Question 3.
Match the Column I with Column II.

Answer:
A. (iii)
B. (iv)
C. (v)
D. (ii)
E. (i)

III. Answer the following questions briefly

Question 1.
What are the features of copper and aluminium?
Answer:

• Malleability
• Expandability
• Good conductor of heat and energy (electricity)

Question 2.
Where was the first hydro-electric power station in India established?
Answer:
The first hydro-electric power station in India was established at “Darjeeling” in 1897.

Question 3.
In which type of rocks is limestone found?
Answer:
Limestone is found in sedimentary rocks.

Question 4.
What is the origin of the word petroleum?
Answer:
The word petroleum is derived from two Latin words petro (Rock) and Oleum (oil) thus petroleum is oil obtained from rocks of the earth. It is also called as mineral oil.

Question 5.
Name any five software centres.
Answer:

1. Chennai
2. Bangalore
3. Mysore
4. Hyderabad
5. Coimbatore

Question 6.
When was the Nuclear power programme initiated in India and where was the first Atomic Power station was set up?
Answer:

1. Nuclear Power programme was initiated in the 1940s, when “ Tata Atomic Research Commission was incorporated in August 1948.
2. The 1st nuclear power station was set up at Tarapur near Mumbai in 1969.

Question 7.
What are the raw materials for the paper industry?
Answer:
Woodpulp, bamboo, salai, Sabai grasses, waste paper and bagasse

Question 8.
Write a note on NPCIL.
Answer:

1. The Nuclear Power Corporation of India Limited ( NPCIL) is wholly owned by the Government of India.
2. It is a Public sector undertaking.
3. Responsible for the generation of nuclear power for electricity.
4. Administered by the Department of Atomic Energy (DAE). It is responsible for designing, constructing and operating the Nuclear power stations in India.

Question 9.
What are the major centres of the automobile industry?
Answer:
Mumbai, Chennai, Kolkata, New Delhi, Pune, Ahmedabad, Lucknow, Satara and Mysore.

Question 10.
Where are the centres of IT parks located in India?
Answer:
Centres of IT parks in India are located in Chennai, Coimbatore, Thiruvananthapuram, Bengaluru, Mysuru, Hyderabad, Vishakapatnam, Mumbai, Pune, Indore, Gandhinagar, Jaipur, Noida, Mohali and Srinagar.

IV. Distinguish between

Question 1.
Paper industry and Iron and Steel industry.
Answer:
Paper industry

1. Forest-based industry.
2. Serve as an index for education and literacy.
3. Wood pulp, Bamboo, bagasse are some of the basic raw materials.

Iron and Steel industry:

1. Mineral-based industry.
2. Key industry for industrial development.
3. Iron ore and Manganese are the main raw materials.

Question 2.
Solar and Wind energy.
Answer:
Solar energy:

1. Conversion of sunlight into electricity.
2. Photo voltoic cells or use of lenses, mirror and tracking system is used.
3. Installation cost is more and different applications is required as per the need.
4. Occupy more space.

Wind energy:

1. Conversion of energy is from the flow of wind.
2. Wind turbines are used.
3. Installation cost is comparatively less.
4. Occupy less space.

Question 3.
Difference between Manganese and Mica.
Answer:
Manganese:

1. It is a Metallic mineral.
2. Very hard and brittle in nature.
3. Raw material for iron and steel basic raw material for alloying.

Mica:

1. It is a Non-Metallic mineral.
2. Translucent, splitable into thin sheets, elastic and incompressible.
3. Exclusively used in electrical goods and also for making lubricants, paints, varnishes etc.

Question 4.
Iron and Steel industry and Software industry.
Answer:
Iron and Steel industry:

1. Age old industry.
2. Depend upon minerals.
3. Large scale industry.
4. Began in 1907.

Software industry:

1. Recently developed industry.
2. Depend upon skill and knowledge (technical).
3. Small and medium scale industry.
4. Began in 1970.

V. Answer the following in a paragraph

Question 1.
Enumerate the automobile industry as the fast-growing industry of India.
Answer:
The first automobile industry was established at the Premier Automobiles Ltd at Kurla (Mumbai) in 1947 and the Hindustan Motor Ltd at Uttarpara (Kolkata) in 1948. At present India is the 7th largest producer of automobile manufactures which includes two wheelers, commercial vehicles, passenger cars, Jeep, scooty, scooters, motor cycles mopeds and three wheelers.

Among the production of two wheelers, motorcycles are manufactured at Faridabad, Haryana and Mysore. While scooters are manufactured at Lucknow, Satara, Akudi (Pune), Panki (Kanpur) and Odhai (Ahmedabad). The cars produced at Haryana, Kolkata, Mumbai and Chennai are Maruti, Ambassador, Fiat, Ford and Hyndai etc. Presenceof foreign car companies such as Mercedes Benz, Fiat, General Motors, Toyota and the recent entry of passenger cars manufacturers BMW, Audi, Volks Wagen and Volvo makes the Indian automobile sector a special one.

Several new joint venture agreements for the manufacture of cars have recently been signed by the Indian companies and renowned car manufacturers of the world. The Indian auto industry is said to take a big leep in the near fixture. This expected to provide much more competitive environment to the industry and a wide choice of ultra modem cars to the consumers. This is the fast growing industry in India.

Question 2.
What are the different forms of Iron ore and their nature?
Answer:
Iron ores are rocks and minerals from which metallic iron can be economically extracted.

The different forms of Iron ore are:

Form of Iron ores	Iron content %
Magnetite	72.4%
Haemetite	69.9%
Goethite	62.9%
Limonite	55%
Siderite	48.2%

Nature: The ores are usually rich in iron oxides and vary in colour from dark grey, bright yellow or deep purple to rusty red.

Question 3.
Write about the uses of Coal and its areas of distribution.
Answer:

1. Coal is a non-renewable resource. It is available in the form of sedimentary rocks.
2. It has close association with the industrial development of any country.

Uses: Coal is an important source of energy in India with its varied and innumerable uses

1. It is converted into gas, oil and thermal power electricity.
2. Besides it forms a basic raw materials for the production of chemicals, dyes, fertilizers, paints, synthetic and explosives.
3. Distribution: Indian coal is mostly associated with Gondwana region and is primarily found in peninsular India.
4. The States of Jharkhand, Odisha, West Bengal and Madhya Pradesh alone account for nearly 90% of coal reserves of the country. About 2% of India’s coal is of tertiary type and is mostly in Assam and Jammu and Kashmir.
5. Jharkhand is the largest coal producing state in the country. Indian lignite (brown coal) deposits occur particularly in Tamil Nadu ( Neyveli), Puducherry and Kerala.

Question 4.
Give an account on Automobile industry in India.
Answer:
Automobile industry’ is one of the most dynamic industrial groups in India. India is the 7th largest producer of automobile manufacturers.

Distribution: The automobile industries are found in four clusters viz: Delhi, Gurgaon and Manesar in North India.

West India: Pune, Nasik, Halol and Aurangabad East India: Jamshedpur and Kolkatta South India: Chennai, Bengaluru and Hosur.

Major-Indian companies which manufacture commercial vehicles: Tata motors, Ashok Leyland, Mahindra and Mahindra, Eicher motors and Ford motors.

Foreign companies which manufacture commercial vehicles: Hyundai, Mercedes Benz , ITEC, MAN.

Automobile industries in India manufactures two wheelers passenger car, Jeep, Scooty, Scooter, Mopeds, Motorcycles and three wheelers.

Passenger car manufacturers: Tata motors, Maruti Suzuki , Mahindra and Mahindra and Hindustan motors are Indian companies.

Foreign car companies in India: Mercedez Benz, Fiat, General motors, Toyota, recent entry BMW, Audi, Volkswagon and Volvo.

Two wheeler manufacturing is dominated by Indian companies like Hero, Bajaj Auto and TVS.

Major centres of Automobile industries: Mumbai, Chennai, Jamshedpur, Jabalpur, Kolkata, Pune, New Delhi, Kanpur, Bengaluru, Satara, Lucknow • and Mysuru. Chennai is named as “Detroit of Asia” due to the presence of major automobile manufacturing units and allied industries around the city.

Question 5.
What are the major challenges faced by the Indian industries?
Answer:
Some major challenges faced by industries in India are:

1. Non-availability of large blocks of land.
2. Shortage and fluctuation in power supply.
3. Non-availability of cheap labourers.
4. Poor access to credit.
5. High rate of interest for borrowed loan.
6. Lack of technical and vocational training for employees.
7. In appropriate living conditions nearby industrial areas.

VI. On the outline map of India mark the following

Question 1.
Any two places producing limestone
Answer:

Question 2.
Any two Nuclear power stations
Answer:

Question 3.
Any two Thermal power stations in Tamil Nadu
Answer:

Question 4.
Wind farm places (any 2)
Answer:

Students can download 10th Science Chapter 10 Types of Chemical Reactions Questions and Answers, Notes, Samacheer Kalvi 10th Science Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

Tamilnadu Samacheer Kalvi 10th Science Solutions Chapter 10 Types of Chemical Reactions

Samacheer Kalvi 10th Science Types of Chemical Reactions Text Book Back Questions and Answers

I. Choose the correct answer:

Question 1
H_2(g) + Cl_29(g) → 2HCl_(g)
(a) Decomposition Reaction
(b) Combination Reaction
(c) Single Displacement Reaction
(d) Double Displacement Reaction
Answer:
(a) Decomposition Reaction

Question 2.
Photolysis is a decomposition reaction caused by ______.
(a) heat
(b) electricity
(c) light
(d) mechanical energy
Answer:.
(c) light
Hint:
\(2 \mathrm{AgBr}_{(\mathrm{s})} \stackrel{\mathrm{Light}}{\longrightarrow} 2 \mathrm{Ag}_{(\mathrm{s})}+\mathrm{Br}_{2(\mathrm{g})}\)

Question 3.
A reaction between carbon and oxygen is represented by C_(s) + O_2(g) → CO_2(g) + Heat. In which of the type(s), the above reaction can be classified?
(i) Combination Reaction
(ii) Combustion Reaction
(iii) Decomposition Reaction
(iv) Irreversible Reaction
(a) (i) and (ii)
(b) (i) and (iv)
(c) (i), (ii) and (iii)
(d) (i), (ii) and (iv)
Answer:
(d) (i), (ii) and (iv)

Question 4.
The chemical equation \(\mathrm{Na}_{2} \mathrm{SO}_{4(\mathrm{aq})}+\mathrm{BaCl}_{2(\mathrm{aq})} \rightarrow \mathrm{BaSO}_{4(\mathrm{s})} \downarrow+2 \mathrm{NaCl}_{(\mathrm{aq})}\) represents which of the following types of reaction?
(a) Neutralisation
(b) Combustion
(c) Precipitation
(d) Single displacement.
Answer:
(c) Precipitation
Hint: This reaction involves the precipitation of white BaSO₄ by mixing of Na₂SO₄ (aq) and BaCl₂ (aq). Hence it belongs to precipitation reaction.

Question 5.
Which of the following statements are correct about a chemical equilibrium?
(i) It is dynamic in nature
(ii) The rate of the forward and backward reactions are equal at equilibrium
(iii) Irreversible reactions do not attain chemical equilibrium
(iv) The concentration of reactants and products may be different
(a) (i), (ii) and (iii)
(b) (i), (ii) and (iv)
(c) (ii), (iii) and (iv)
(d) (i), (iii) and (iv)
Answer:
(a) (i), (ii) and (iii)

Question 6.
A single displacement reaction is represented by \(\mathrm{X}_{(\mathrm{s})}+2 \mathrm{HCl}_{(\mathrm{aq})} \rightarrow \mathrm{XCl}_{2(\mathrm{aq})}+\mathrm{H}_{2(\mathrm{g})}\). the following(s) could be X?
(i) Zn
(ii) Ag
(iii) Cu
(iv) Mg.
Choose the best pair.
(a) i and ii
(b) ii and iii
(c) iii and iv
(d) i and iv.
Answer:
(d) i and iv.
Hint:
Zn + 2HCl → ZnCl₂ + H₂
Mg + 2HCl → MgCl₂ + H_2.

Question 7.
Which of the following is not an “element + element → compound” type reaction?
(a) C_(s) + O_2(g) → CO_2(g)
(b) 2K_(s) + Br_2(l) → 2KBr_(s)
(c) 2CO_(g) + O_2(g) → 2CO_2(g)
(d) 4Fe_(s) + 3O_2(g) → 2Fe₂O_3(s)
Answer:
(c) 2CO_(g) + O_2(g) → 2CO_2(g)

Question 8.
Which of the following represents a precipitation reaction?
(a) A_(s) + B_(s) → C_(s) + D_(s)
(b) A_(s) + B_(aq) → C_(aq) + D_(l)
(c) A_(aq) + B_(aq) → C_(s) + D_(aq)
(d) A_(aq) + B_(s) → C_(aq) + D_(l)
Answer:
(c) A_(aq) + B_(aq) → C_(s) + D_(aq)

Question 9.
The pH of a solution is 3. Its [OH^–] concentration is ______.
(a) 1 × 10^-3 M
(b) 3 M
(c) 1 × 10^-11 M
(d) 11 M.
Answer:
(c) 1 × 10^-11 M
Hint: pH = 3
It means [H⁺] = 10^-3
[H⁺] [OH^–] = 10^-14
[10^-3] [OH^–] = 10^-14
[OH^–] = 10^-11

Question 10.
Powdered CaCO₃ reacts more rapidly than flaky CaCO₃ because of :
(a) large surface area
(b) high pressure
(c) high concentration
(d) high temperature
Answer:
(a) large surface area

II. Fill in the blanks:

1. A reaction between an acid and a base is called ………..
2. When zinc metal is placed in hydrochloric acid, ………. gas is evolved.
3. The equilibrium attained during the meiting of ice is known as ………..
4. The pH of a fruit juice is 5.6. If you add slaked lime to this juice, its pH ……….
5. The value of ionic product of water at 25 °C is ………..
6. The normal pH of human blood is …………
7. Electrolysis is type of ……….. reaction.
8. The number of products formed in a synthesis reaction is ………..
9. Chemical volcano is an example for ……….. type of reaction.
10. The ion formed by dissolution of H⁺ in water is called …………
Answer:
1. neutralization
2. H₂
3. physical equilibrium
4. increases to ‘7’
5. 1 × 10^-14 mol² dm^-6
6. 7.4
7. decomposition
8. 1
9. decomposition
10. hydronium ion

III. Match the following:

Question 1.
Identify the types of reaction:

Answer:
A. (iii)
B. (i)
C. (iv)
D. (ii)

IV. True or False: (If false give the correct statement)

1. Silver metal can replace hydrogen gas from nitric acid.
2. The pH of rain water containing dissolved gases like SO₃, CO₂, NO₂ will be less than 7.
3. At the equilibrium of a reversible reaction, the concentration of the reactants and the products will be equal.
4. Periodical removal of one of the products of a reversible reaction increases the yield.
5. On dipping a pH paper in a solution, it turns into yellow. Then the solution is basic.

Answer:

1. False – Silver cannot displace H₂ from HNO₃ acid, since it is placed below hydrogen in the activity series.
2. True
3. False – At equilibrium the concentration of the reactants and products do not change it remains constant, but the concentration of the reactants and the products will not be equal.
4. True
5. False – The solution is neutral if the solution is basic it will be green in colour.

V. Short answer questions:

Question 1.
When an aqueous solution of potassium chloride is added to an aqueous solution of silver nitrate, a white precipitate is formed. Give the chemical equation of this reaction.
Answer:

Question 2.
Why does the reaction rate of a reaction increase in raising the temperature?
Answer:
On increasing temperature heat is supplied to the reactant. This energy breaks more bonds and thus speed up the chemical reaction. Foods kept at room temperature spoils faster than that kept in the refrigerator.

Question 3.
Define combination reaction. Give one example for an exothermic combination reaction.
Answer:
A combination reaction is a reaction in which two or more reactants combine to form a compound.
Eg: C_(s) + O_2(g) → CO_2(g) + heat

Question 4.
Differentiate reversible and irreversible reactions.
Answer:

VI. Answer in detail:

Question 1.
What are called thermolysis reactions?
Answer:
Thermal decomposition reactions are called ‘thermolysis’ reaction. In this type of reaction, the reactant is decomposed by applying heat. There are two types of thermolysis reactions. They are:
(i) Compound to element / element decomposition:
A compound is decomposed into two elements.
Eg:

(ii) Compound to compound / compound decomposition:
A compound is decomposed into two compounds.
Eg:

Question 2.
Explain the types of double displacement reactions with examples.
Answer:
There are two major classes of double displacement reactions. They are,
(i) Precipitation Reactions: When aqueous solutions of two compounds are mixed, if they react to form an insoluble compound and a soluble compound, then it is called precipitation reaction.
\(\mathrm{Pb}\left(\mathrm{NO}_{3}\right)_{2(\mathrm{aq})}+2 \mathrm{KI}_{(\mathrm{aq})} \rightarrow \mathrm{PbI}_{2(\mathrm{s})} \downarrow+2 \mathrm{KNO}_{3(\mathrm{aq})}\)

(ii) Neutralisation Reactions: Another type of displacement reaction in which the acid reacts with the base to form a salt and water. It is called ‘neutralisation reaction’ as both acid and base neutralize each other.
\(\mathrm{NaOH}_{(\mathrm{aq})}+\mathrm{HCl}_{(\mathrm{aq})} \rightarrow \mathrm{NaCl}_{(\mathrm{aq})}+\mathrm{H}_{2} \mathrm{O}_{(\mathrm{l})}\).

Question 3.
Explain the factors influencing the rate of a reaction.
Answer:
Important factors that affect rate of a reaction are:

1. Nature of the reactants
2. Concentration of the reactants
3. Temperature
4. Catalyst
5. Pressure
6. Surface area of the reactants

1. Nature of the reactants : The reaction of sodium with hydrochloric acid is faster than that with acetic acid, because Hydrochloric acid is a stronger acid than acetic acid and thus more reactive. So, the nature of the reactants influence the reaction rate.
2Na_(s) + 2HCl_(aq) → 2NaCl_(aq) + H_2(g) (fast)
2Na_(s) + 2CH₃COOH_(aq) → 2CH₃COONa_(aq) + H_2(g) (slow)

2. Concentration of the reactants : Changing the amount of the reactants also increases the reaction rate. More the concentration, more particles per volume exist in it and hence faster the reaction. Granulated zinc reacts faster with 2M hydrochloric acid than 1M hydrochloric acid.

3. Temperature : Most of the reactions go faster at higher temperature. Because adding heat to the reactants provides energy to break more bonds and thus speed up the reaction. Calcium carbonate reacts slowly with hydrochloric acid at room temperature. When the reaction mixture is heated the reaction rate increases.

4. Pressure : If the reactants are gases, increasing their pressure increases the reaction rate. This is because, on increasing the pressure the reacting particles come closer and collide frequently.

5. Catalyst : A catalyst is a substance which increases the reaction rate without being consumed in the reaction. In certain reactions, adding a substance as catalyst speeds up the reaction. For example, on heating potassium chlorate, it decomposes into potassium chloride and oxygen gas, but at a slower rate. If manganese dioxide is added, it increases the reaction rate.

6. Surface area of the reactants : Powdered calcium carbonate reacts more readily with hydrochloric acid than marble chips. Because, powdering of the reactants increases the surface area and more energy is available on collision of the reactant particles. Thus, the reaction rate is increased.

Question 4.
How does pH play an important role in everyday life?
Answer:

• The pH of blood is almost 7.4. Any increase or decrease in this value leads to diseases
• Citrus fruits require slightly alkaline soil, while rice requires acidic soil and sugarcane requires neutral soil.
• If the pH of rainwater becomes less than 7, it becomes acid rain which is harmful in day-to-day life.
• pH changes cause tooth decay.
• During indigestion, the stomach produces too much acid and this causes pain and irritation.

Question 5.
What is chemical equilibrium? What are its characteristics?
Answer:
Chemical equilibrium is a state of a reversible chemical reaction where the,
Rate of forward reaction = Rate of backward reaction.
No change in the amount of the reactants and products takes place.
Characteristics of equilibrium:

1. In a chemical equilibrium, the rates of the forward and backward reactions are equal.
2. The observable properties such as pressure, concentration, colour, density, viscosity etc., of the system remain unchanged with time.
3. The chemical equilibrium is a dynamic equilibrium, because both the forward and backward reactions continue to occur even though it appears static externally.
4. In physical equilibrium, the volume of all the phases remain constant.

VII. HOT Questions:

Question 1.
A solid compound ‘A’ decomposes on heating into ‘B’ and a gas ‘C’ On passing the gas ‘C’ through water, it becomes acidic. Identify A, B and C.
Answer:
A – CaCO₃, solid compound
‘A’ decomposes on heating into ‘B’ and a gas ‘C’.

On passing the gas CO₂ through water, it becomes acidic.

A – CaCO₃, Calcium carbonate
B – CaO, Calcium oxide
C – CO₂, Carbondioxide gas

Question 2.
Can a nickel spatula be used to stir copper sulphate solution? Justify your answer.
Answer:
No, nickel spatula cannot be used to stir the copper sulphate solution. Actually, on the basis of activity series, nickel is more reactive than copper, so nickel will displace copper from its solution and copper will be deposited on nickel spatula.

VIII. Solve the following problems:

Question 1.
Lemon juice has a pH 2, what is the concentration of H⁺ ions?
Answer:
pH = – log [H⁺]
[H⁺] = antilog of [-pH]
= antilog [-2]
[H⁺] = 10^-2 M
[OR]
PH = – log [H⁺]
[H⁺] = 10^-pH
[H⁺] = 10^-2M

Question 2.
Calculate the pH of 1.0 × 10^-4 molar solution of HNO₃.
Answer:
pH = – log [H⁺]
HNO3 → H⁺ + NO₃^–
pH = -log [1 × 10^-4]
= -(-4)log₁₀ 10 = 4
pH = 4

Question 3.
What is the pH of 1.0 x 10^-5 molar solution of KOH?
Answer:
KOH → K⁺ + OH^–
pOH = -log[OH^–]
= -log [1 × 10^-5]
pOH = 5
pH + pOH = 14
∴ pH of KOH = 14 – 5 = 9
pH = 9

Question 4.
Laundry detergent has a pH 8.5, What is the concentration of H⁺ ions?
Answer:
pH = 8.5
pH = – log [H⁺]
[H⁺] = 10^-pH
[H⁺] = 10^-8.5
[H⁺] = 3.16 × 10^-9 M

Question 5.
The hydroxide ion concentration of a solution is 1 × 10^-11M. What is the pH of the solution?
Answer:
[OH^–] = 1 × 10^-11 M
pOH = – log[OH^–]
= – log[1 × 10^-11]
= -log₁₀1 – log₁₀10^-11
= -(-11) log₁₀10 = 11
pOH = 11
pH + pOH = 14
pH = 14 – 11
pH = 3

Samacheer Kalvi 10th Science Types of Chemical Reactions Additional Important Questions and Answers

I. Choose the correct answer:

Question 1.
The unit of rate of a reaction is:
(a) dm³/mol
(b) dm^-3
(c) mol dm^-3
(d) mol
Answer:
(c) mol dm^-3

Question 2.
As the molecule is dissociated by the absorption of heat it is otherwise called as ______.
(a) Thermolysis
(b) Photolysis
(c) Electrolysis
(d) None of these.
Answer:
(a) Thermolysis

Question 3.
The chemical formula of marble is:
(a) CaCO₃
(b) MgCO₃
(c) Na₂CO₃
(d) PbCO₃
Answer:
(a) CaCO₃

Question 4.
As the decomposition is caused by light, this kind of reaction is called ______.
(a) Thermolysis
(b) Photolysis
(c) Electrolysis
(d) None of these.
Answer:
(b) Photolysis

Question 5.
Fluorine will displace the following halide ion from the solution:
(a) chloride
(b) bromide
(c) iodide
(d) all the above
Answer:
(d) all the above

Question 6.
The decomposition of AgBr into grey coloured silver metal is an example of ……… reaction.
(a) compound to element/element
(b) compound to compound/compound
(c) combination
(d) neutralization
Answer:
(a) compound to element/element

Question 7.
The Metathesis reaction among the following is:
(a) C₃H_8(g) +5O_2(g) → 3CO_2(g) + 4H₂O + heat
(b) Zn_(s) + CuSO_4(aq) → ZnSO_4(aq) + Cu_(s)
(c) HNO_3(aq) + NH₄OH_(aq) → NH₄NO_3(aq) + H₂O_(l)

Answer:
(c) HNO_3(aq) + NH₄OH_(aq) → NH₄NO_3(aq) + H₂O_(l)

Question 8.
KI and Pb(NO₃)₂ solutions are mixed to give a precipitate. What is the colour of the precipitate?
(a) White
(b) Brown
(c) Red
(d) Yellow.
Answer:
(d) Yellow

Question 9.
The pH of rain water is approximately:
(a) 7
(b) 8
(c) 4
(d) 14
Answer:
(a) 7

Question 10.
Most of the reactions go faster at ______.
(a) low temperature
(b) moderate temperature
(c) 0°C
(d) high temperature.
Answer:
(d) high temperature

II. Fill in the blanks.

1. A chemical equation provides information on the ……….. of the substances and the reaction condition.
2. The symbol ‘aq’ in a chemical equation represent the physical state of the substance as ……….
3. 2Na_(s) + Cl_2(g) → 2NaCl_(s) represent the combination reaction between a ……… and ……
4. After white washing with a solution of slaked lime a thin layer of ……….. is formed.
5. Reactions in which heat is absorbed is called ……….. reactions.
6. Electrolytic refining of copper is based on ……….. reaction.
7. When 10^-6 mole of a monobasic strong acid is dissolved in water, the pH of the solution is ………..
8. When pH of a solution is 2, the [H⁺] in mol/L is ……….
9. Combustion of coal is an example of ………. reaction.
10. [ ] represents the concentration of either the reactant or product in ……….
Answer:
1. physical state
2. aqueous solution
3. metal, non-metal
4. CaCO₃
5. endothermic
6. electrolytic decomposition
7. 6
8. 1 × 10^-2
9. irreversible
10. mol/Lit

III. Match the following.

Question 1.
Match the following table:

Answer:
A. (v)
B. (iii)
C. (iv)
D. (ii)
E. (i)

Question 2.
Match the following table:

Answer:
A. (v)
B. (iv)
C. (i)
D. (iii)
E. (ii)

Question 3.
Match the following table:

Answer:
A. (iii)
B. (v)
C. (iv)
D. (ii)
E. (i)

Question 4.
Match the following table:

Answer:
A. (iv)
B. (v)
C. (i)
D. (ii)
E. (iii)

IV. True or False: (if false give the correct statement)

1. Formation of calcium silicate from silica and calcium oxide is a combination reaction.
2. Most of the combination reactions are endothermic in nature.
3. Decomposition of mercuric oxide into mercury and O₂ is an example of . photolysis.
4. Chlorine can displace fluoride ion from its aqueous solution.
5. Magnesium is more reactive than iron.

Answer:

1. True
2. False – Most of the combination reactions are exothermic in nature.
3. False – Decomposition of mercuric oxide into mercury and O₂ is an example of thermolysis.
4. False – Chlorine is less reactive than Fluorine, so it cannot displace fluoride ion from its aqueous solution.
5. True

V. Short answer questions:

Question 1.
Write a note on double displacement reaction with an example.
Answer:
When two compounds react, if their ions are interchanged, then the reaction is called double displacement reaction.
Eg: NaOH_(aq) + HCl_(aq) → NaCl_(aq) + H₂O

Question 2.
Identify the wrong statements and correct them.

1. Sodium benzoate is used in food preservative.
2. Nitric acid is not used as fertilizer in agriculture.
3. Sulphuric acid is called the king of chemicals.
4. The pH of acid is greater than 7.
5. Acetic acid is used in aerated drinks.

Answer:

1. Correct statement.
2. Wrong statement. Nitric acid is used as a fertilizer in agriculture.
3. Correct statement.
4. Wrong statement. The pH of the acid is lesser than 7.
5. Wrong statement. Carbonic acid is used in aerated drinks.

Question 3.
Why a combustion reaction may be called as an exothermic oxidation?
Answer:
In a combustion reaction heat is evolved, it is an exothermic reaction. As oxygen is added, it is also an oxidation. So, combustion may be called as an exothermic oxidation.

Question 4.
Take two conical flasks. Label them as I and II. Take a small amount of copper sulphate solution in the first conical flask. Take a small amount of granulated zinc in the second conical flask. Allow the copper sulphate solution to react with the zinc.

1. Name the type of reaction.
2. Say whether the metal zinc is more reactive or less reactive.
3. Write a complete and balanced reaction.
4. Say whether this change is reversible or irreversible.

Answer:

1. The reaction taken place is displacement reaction.
2. Metal zinc is more reactive.
3. Balanced chemical equation.
   \(\mathrm{Zn}_{(\mathrm{s})}+\mathrm{CuSO}_{4(\mathrm{aq})} \rightarrow \mathrm{ZnSO}_{4(\mathrm{aq})}+\mathrm{Cu}_{(\mathrm{s})} \downarrow\)
4. This change is an irreversible change.

Question 5.
What is an irreversible reaction? Give an example.
Answer:
The reaction that cannot be reversed is called irreversible reaction. The irreversible reactions are unidirectional, i.e., they take place only in the forward direction. Consider the combustion of coal into carbon dioxide and water.

Question 6.
Define the rate of a reaction.
Answer:
“Rate of a reaction is the change in the amount or concentration of any one of the reactants or products per unit time”.
Consider the following reaction,
A → B
The rate of this reaction is given by
Rate = –\(\frac{d[A]}{dt}\) = +\(\frac{d[B]}{dt}\)
Where,
[A] – Concentration of A
[B] – Concentration of B
The negative sign indicates the decrease in the concentration of A with time. The positive sign indicates the increase in the concentration of B with time.

Question 7.
What is meant by combination reaction? Give an example.
Answer:
A reaction in which a single product is formed from two or more reactants is known combination reaction.
2Mg + O₂ → 2MgO.

Question 8.
What is a catalyst?
Answer:
A catalyst is a substance which increases the reaction rate without being consumed in the reaction.

Question 9.
Define Displacement reaction. Give an example.
Answer:
The reaction in which a more reactive element displaces a less reactive element from its compound is called displacement reaction.
\(\mathrm{Pb}+\mathrm{CuCl}_{2} \longrightarrow \mathrm{PbCl}_{2}+\mathrm{Cu} \downarrow\)
Lead displaces copper from copper chloride solution.

Question 10.
When a aerated soft drink bottle is kept open it will go flat. Why?
Answer:
(i) In the sealed aerated soft drink bottle, the dissolved CO₂, in the form of carbonic acid and gaseous CO₂ are in equilibrium.
(ii) When we open the bottle the gaseous CO₂ will escape and the dissolved CO₂ begins to undissolve to the gas phase to maintain the equilibrium. So when we keep the bottle open for a long time it will go flat with all the dissolved CO₂ gone.

Question 11.
Can copper displace zinc or lead from their salt solutions?
Answer:
No, copper cannot displace zinc or lead from their salt solutions. Because copper is less reactive than zinc and lead.

Question 12.
What is called as acid rain?
Answer:
The pH of rain water is approximately ‘7’ but when the air is polluted with oxides of S and N, they get dissolved in the rain water and make its pH less than 7, then it is called acid rain.

Question 13.
Write the differences between combination and decomposition reaction.
Answer:

VI. Answer in detail:

Question 1.
Two acids ‘A’ and ‘B’ were kept in beakers. Acid ‘A’ undergoes partial dissociation in water, whereas acid ‘B’ undergoes complete dissociation in water.

1. Of the two acids ‘A’ and ‘B’ which is weak acid and which is strong acid?
2. What is a weak acid?
3. What is a strong acid?
4. Give one example of each.

Answer:

1. Of the two acids ‘A’ and ‘B’, ‘A’ is a weak acid and ‘B’ is a strong acid.
2. A weak acid is the one which ionises partially when dissolved in water.
3. A strong acid is the one which ionises completely when dissolved in water.
4. Weak acid – Acetic acid(CH₃COOH)
   Strong acid – Sulphuric acid (H₂SO₄).

Question 2.
Sodium hydroxide and HCl acid react as shown in this equation
NaOH_(aq)4 + HCl_(aq) → NaCl_(aq) + H₂O
(i) Which type of chemical reaction is this?
Answer:
Neutralization reaction

(ii) The reaction is exothermic. Explain what that means?
Answer:
When heat is evolved during a chemical reaction it is called exothermic.

(iii) Differentiate exothermic and endothermic reaction.
Answer:
Exothermic :

1. Heat is evolved.
2. Temperature increases.

Endothermic :

1. Heat is absorbed.
2. Temperature decreases.

(iv) What happens to the temperature of the solution as the chemicals react?
Answer:
Temperature of the solution increases.

Question 3.
Take two conical flasks. Label them as I and II. Take a small amount of CuSO₄ in the I conical flask and small amount of granulated Zinc in the II conical flask. Allow the CuSO₄ solution to react with Zinc.
(i) Name the type of reaction.
Answer:
Displacement reaction.

(ii) Say whether the metal Zn is more reactive or less reactive.
Answer:
Zinc is more reactive than Copper.

(iii) Write the complete and balanced reaction.
Answer:
Zn_(s)+ CuSO_4(aq) → ZnSO_4(aq) + Cu_(s)↓

(iv) Say whether this change is reversible or irreversible
Answer:
Irreversible.

Question 4.
Suggest a reason for each observation given below.

1. In fireworks, powdered magnesium is used rather than magnesium ribbon.
2. Zinc and dilute H₂SO₄ react much more quickly when a few drops of copper sulphate solutions are added.
3. The reaction between magnesium carbonate and dilute hydrochloric acid speeds up when some concentrated HCl is added.

Answer:

1. In fireworks, powdered magnesium is used because it has more surface area than magnesium ribbon. Because of more surface area, powdered magnesium reacts faster than magnesium ribbon.
2. Zinc and dilute H2SO4 react much more quickly when a few drops of copper sulphate solution is added. Copper sulphate acts as a catalyst which increases the rate of the reaction.
3. When the concentration of the reactants increases, the rate of the reaction also increases. So the reaction between magnesium carbonate and dilute hydrochloric acid speeds up by the addition of some concentrated HCl.

VII. Hot Questions:

Question 1.

Answer:
According to the rate Law for the reaction.
2N₂O₅ → 4NO₂ + O₂

2K₁ = K₂ = 4K₃ [neglecting negative and positive signs]

Question 2.
When solutions of silver nitrate and potassium bromide are mixed, a pale yellow precipitate is formed.
The ionic equation for the reaction is Ag⁺ + Br^– → AgBr

1. (a) What is the name of the pale yellow precipitate?
   (b) Is it soluble or insoluble?
2. Is the formation of silver bromide precipitate, a result of redox reaction or not? Justify your answer.
3. What is this type of reaction called?

Answer:

1. (a) The pale yellow precipitate is silver bromide.
   (b) Silver bromide is sparingly soluble.
2. Yes, the formation of silver bromide precipitate is due to redox reaction. Ag⁺ gains electron (reduction) and Br^– loses electron (oxidation). So it is a redox reaction.
3. This reaction is a double displacement reaction.

VIII. Numericals:

Question 1.
The hydrogen ion concentration of a fruit juice is 3.3 × 10^-2M. What is the pH of the juice? Is it acidic or basic?
Answer:
[H⁺] = 3.3 × 10^-2 M
Formula:
pH = -log[H⁺]
pH = -log[3.3 × 10^-2]
= -[log 3.3 + log 10^-2]
= -[0.5185 – 2 log₁₀10]
= -0.5185 + 2 log₁₀10 [log₁₀10 = 1]
= -0.5185 + 2
pH = 1.4815
Since pH is less than 7, the solution is acidic.

Question 2.
If a solution has a pH of 7.41, determine its H⁺ concentration.
Answer:
pH = 7.41
Formula:
[H⁺] = antilog[-pH]
= antilog[-7.41] = 10^-7.41
= 3.89 × 10^-8M

Question 3.
The pH of a solution is 5.5 at 25°C. Calculate its [OH^–].
Answer:
pH = 5.5
Since pH + pOH = 14
pOH = 14 – pH
= 14 – 5.5 = 8.5
[OH^–] = 10^-pOH
= 10^-8.5
= 3.16 × 10^-9M
(OR)
[OH^–] = antilog[-8.5]
= 3.16 × 10^-9M
[OH^–] = 3.16 × 10^-9M

Question 4.
Calculate the pH of 0.001 M HCl solution.
Answer:
Since HCl is a strong acid, it dissociates
HCl → H⁺ + Cl^–
[H⁺] = [HCl] = 0.001 M
[H⁺] = 1 × 10^-3M
pH = -log[H⁺]
= -log[1 × 10^-3]
pH = 3

Question 5.
The hydrogen ion concentration of a solution is 1 × 10^-8M.
(i) What is the pH of the solution?
Answer:
pH = -log[1 × 10^-8]
pH = 8

(ii) What is the pOH of the solution?
Answer:
pOH = 14 – 8
= 6

(iii) Is the given solution acidic or basic?
Answer:
Acidic

Question 6.
Calculate the pH of 0.02 M Ba(OH)₂, Ba(OH)₂ solution is a strong electrolyte.
Answer:
[Ba(OH)₂] = 0.02 M
Ba(OH)₂ → Ba²⁺ + 2OH^–
[OH^–] = 2[Ba(OH)₂]
= 2 × 0.02 = 0.04 M
pOH = – log[0.04]
= -log[4 × 10^-2]
= -[log 4 + log 10^-2]
= -[0.6020 – 2 log 10]
pOH = -0.6020 + 2 × 1
= 1.398
pH = 14 – 1.398
= 12.602

Students can download 10th Social Science Geography Chapter 3 Components of Agriculture Questions and Answers, Notes, Samacheer Kalvi 10th Social Science Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

Tamilnadu Samacheer Kalvi 10th Social Science Solutions Geography Chapter 3 Components of Agriculture

Samacheer Kalvi 10th Social Science Components of Agriculture Text Book Back Questions and Answers

I. Choose the correct answer

Question 1.
The soil which is rich in iron oxides is
(a) Alluvial
(b) Black
(c) Red
(d) Alkaline
Answer:
(c) Red

Question 2.
Which of the following organization has divided the Indian soils into 8 major groups?
(a) Indian Council of Agricultural Research
(b) Indian Meteorological Department
(c) Soil Survey of India
(d) Indian Institute of Soil Science
Answer:
(a) Indian Council of Agricultural Research

Question 3.
The soils formed by the rivers are:
(a) Red soils
(b) Black soils
(c) Desert soils
(d) Alluvial soils india.
Answer:
(d) Alluvial soils india.

Question 4.
……….. dam is the highest gravity in India.
(a) Hirakud dam
(b) Bhakra Nangal dam
(c) Mettur dam
(d) Nagaijuna Sagar dam
Answer:
(b) Bhakra Nangal dam

Question 5.
……………… is a cash crop.
(a) Cotton
(b) Wheat
(c) Rice
(d) Maize
Answer:
(a) Cotton

Question 6.
Black soils are also called as ………..
(a) Arid soils
(b) Saline soils
(c) Regur soils
(d) Mountain soils
Answer:
(c) Regur soils

Question 7.
The longest dam in the world is:
(a) Mettur dam
(b) Kosi dam
(c) Hirakud dam
(d) Bhakra Nangal dam
Answer:
(c) Hirakud dam

Question 8.
The leading producer of rice in India is ……….
(a) Punjab
(b) Maharashtra
(c) Uttar Pradesh
(d) West Bengal
Answer:
(c) Uttar Pradesh

Question 9.
Which crop is called as “Golden Fibre” in India?
(a) Cotton
(b) Wheat
(c) Jute
(d) Tobacco
Answer:
(c) Jute

Question 10.
The state which leads in the production of coffee is ……….
(a) West Bengal
(b) Karnataka
(c) Odisha
(d) Punjab
Answer:
(b) Karnataka

II. Consider the given statements and choose the right option given below

Question 1.
Assertion (A): Horticulture involves the cultivation of fruits, vegetables, and flowers.
Reason (R): India ranks first in the world in the production of mango, banana, and citrus fruits.
(a) Both (A) and (R) are true and (R) explains (A)
(b) Both (A) and (R)are true: (R) does not explain (A)
(c) (A) is correct (R) is false
(d) (A) is false (R) is true
Answer:
(c) (A) is correct (R) is false

Question 2.
Assertion(A): Alluvial soil is formed by the deposition of eroded and decayed materials brought by the rivers.
Reason(R): Paddy and wheat are grown well in the soil.
(a) Both (A) and (R) are true and (R) explains (A)
(b) Both (A) and (R)are true and (R) does not explain (A)
(c) (A) is correct (R) is false
(d) (A) is false (R) is true
Answer:
(b) Both (A) and (R)are true and (R) does not explain (A)

III. Pick the odd one out

Question 1.
(a) Wheat
(b) Rice
(c) Millets
(d) Coffee
Answer:
(d) Coffee

Question 2.
(a) Khadar
(b) Bhangar
(c) Alluvial soil
(d) Black soil
Answer:
(d) Black soil

Question 3.
(a) Inundation canals
(b) Perennial canals
(c) Tanks
(d) Canals
Answer:
(c) Tanks

IV. Match the following

Answer:
A. (iv)
B. (iii)
C. (v)
D. (i)
E. (ii)

V. Answer in brief

Question 1.
Define soil.
Answer:
Soil is the uppermost layer of the land surface, usually composed of minerals, organic matter, living organisms, air and water. Its formation is mainly related to the parent rock material, surface relief, climate and natural vegetation.

Question 2.
Name the types of soil found in India.
Answer:
There are 8 major groups of soil found in India classified by the Indian Council of Agricultural Research. They are

1. Alluvial soil
2. Black soil
3. Red soil
4. Forest and Mountain soil
5. Arid and Desert soil
6. Laterite soil
7. Saline and Alkaline soil
8. Peaty and Marshy soil

Question 3.
State any two characteristics of black cotton soil.
Answer:

1. This soil is rich in calcium carbonate, magnesium, potash, lime and iron but deficient in phosphorous. It is clayey and impermeable which has great capacity to retain moisture for a long time.
2. It becomes sticky when wet but develops cracks during dry summer season. The soil is suited for dry farming due to its high moisture retentivity.

Question 4.
What is Multipurpose project?
Answer:

1. Multipurpose projects are the River valley projects.
2. Dams are constructed across rivers aims to serve many purposes such as irrigation, power generation, water supply, controlling floods, navigation, development of fisheries etc.

Question 5.
Define Agriculture.
Answer:
Agriculture is the process of producing food for people, fodder for cattle, fiber and many other desired products by the cultivation of certain plants and the raising of domesticated animals

Question 6.
State the types of agriculture practices in India?
Answer:

1. Owing to physical environment and culture the following cultivation systems prevail in India.
2. Subsistence farming
3. Intensive farming
4. Dry farming
5. Mixed farming agriculture
6. Terrace cultivation

Question 7.
Name the seasons of agriculture in India.
Answer:

1. Kharif Season
2. Rabi Season
3. Zaid Season

Question 8.
Mention the plantation crops of India.
Answer:

1. Plantation crops are mainly cultivated for the purpose of exports.
2. These crops are cultivated in large estates on hilly slopes.
3. Tea, coffee, rubber and spices are the main plantation crops of India.

Question 9.
What do you mean by livestock?
Answer:
Livestocks is defined as farm animals who are raised to generate a profile. It is an integral component of the farming system in India.

Question 10.
Write a brief note on the categories of fisheries in India?
Answer:
In India fisheries are categorised into two.They are marine or sea fisheries and inland or fresh water fisheries.

Marine or Sea fisheries:

1. It includes coastal off-shore and deep sea fishing mainly on continental shelf upto a depth of 200 mts.
2. Kerala leads in Marine fish production.

Inland or Fresh water fisheries:

1. Rivers, lakes, canals, reservoirs, ponds tanks etc are the sources of fresh water fisheries,
2. Andhra Pradesh is leading in the fresh water fisheries.
3. About 50% of the country’s total fish production comes from inland fisheries.

VI. Give reasons

Question 1.
Agriculture is the backbone of India.
Answer:
Agriculture provide food for the entire population. It supplies raw materials to the agro-based industries. It contributes to export trade. So, agriculture is the backbone of India.

Question 2.
Rain water harvesting is necessary.
Answer:
India experiences Tropical monsoon climate. Rainfall in India is seasonal, irregular and uneven and highly eractic. Hence it is necessary’ to save rain water when it is available and use in times of need. In order to prevent surface . run off Rainwater harvesting is needed.

Question 3.
Small farms are predominant in India.
Answer:
The predominant type of Indian agriculture is subsistence farming. In this agriculture land holding is small and half of the production is used for family consumption and the rest is sold in the nearby markets. The farmers concentrate on stage food crops like rice and wheat. As the farmers are poor, they can’t apply the modem inputs which cost more.

VII. Distinguish between the following

Question 1.
Rabi and Kharif crop seasons.
Answer:
Rabi crop season:

1. Rabi crop season is from October – March.
2. Seeds are sown in winter and harvested before summer.
3. Major crops of this season are mainly Wheat, Mustard, Maize etc.

Kharif crop season:

1. Kharif crop season is from June – September.
2. Seeds are sown after the summer monsoon and harvested before winter.
3. Major crops are Rice, Cotton, Groundnut, Turmeric etc.

Question 2.
Inundation canal and perennial canal.
Answer:
Inundation canal:

1. Undependable source of irrigation.
2. Operational only during flood in rivers and not have weir system to regulate water.

Perennial canal:

1. Dependable source of irrigation.
2. Have weir system through barrage to regulate water from perennial rivers or dams.

Question 3.
Marine fishing and Inland fishing.
Answer:
Marine fishing:

1. Marine fishing includes coastal, off¬shore and deep sea fishing mainly on the continental shelf upto a depth of 200m.
2. Kerala is the leading producer in marine fishing.

Inland fishing:

1. Inland fishing is done in rivers, lakes, canals, ponds, tanks, reservoirs etc.
2. Andhra Pradesh, West Bengal, Gujarat, Kerala and TamilNadu are the leading states.

Question 4.
Alluvial soils and Black soils.
Answer:
Alluvial soil:

1. Formed by the sediments deposited by the rivers and streams.
2. Silt clay, sandy and loamy in nature.
3. Found in the river valleys and plains.
4. Rice, wheat, sugarcane grow well in this soil.

Black soil:

1. Formed by the disintegration of basalt rocks.
2. Sticky when wet develops cracks when dry.
3. Found in plateau region especially in Deccan trap.
4. Cotton, sugarcane and tobacco grow well in this soil.

VIII. Answer in a paragraph

Question 1.
State the types of soil in India and explain the characteristics and distribution of soil.
Answer:

Question 2.
Write about any two multipurpose projects of India.
Answer:
A comprehensive river valley project which serves a number of purposes simultaneously is called a “Multi purposes project”.

1. The Bhakra Nangal Project: India’s biggest multipurpose river valley project is ‘Bhakra Nangal Project’. It has been built at a strategic point where two hills on either side of the Sutlej are very close to each other. It is the highest gravity dam in the world. Its length is 226 metres from the river bed. The canals taken out are 1100 kilometres long. The ‘Nangal Power Plant’ on the Sutlej produces electricity, and serves the states of Himachal Pradesh, Punjab, Haryana, Rajasthan and New Delhi. The distributaries are 8400 km in length. It irrigates an area of 1.4 million hectares.

2. Indira Gandhi Project: This project is an ambitious scheme to bring new areas under irrigation so that more areas could be cultivated. The waters of the River Beas and the Ravi are diverted to the River Sutlej. The ‘Pong’ Dam on the River Beas has been constructed to divert the Beas water into the Sutlej in a regulated manner. So that ‘Rajasthan canal’, the longest irrigation canal in the world can irrigate Gandhi Nagar, Bikaner and Jaisalmer districts of North West Rajasthan, (i.e) a part of Thar desert. The main canal now called ‘Indira Gandhi Canal’ is 468 km long runs entirely in Rajasthan, Western of Sutlej, Beas and Ravi are now being fully utilised for irrigating thirsty lands of South Western parts of our country.

Question 3.
Bring out the characteristics of intensive and Plantation farming.
Answer:
Characteristics of Intensive farming:

1. Farming is done with intensification and mechanisation system to maximize yields from available land.
2. In this farming heavy use of pesticides and chemical fertilizers have been applied.
3. It has also been applied to the raising of live stock being held indoor as factory farms.
4. Plantation fanning.
5. Single crop raised on a large area testates).
6. Crops are grown mainly for export purpose,
7. The plantations are mostly owned by companies.

Question 4.
Examine the geographical conditions favourable for the cultivation of rice and wheat.
Answer:
Rice:
Rice is an indigenous crop. India is the second-largest producer of rice in the world. It is a tropical crop which is grown well in alluvial plains and river deltas. It requires a mean monthly temperature of 24°C and an average rainfall of 150 cm and deep fertile alluvial soil for its growth. It also needs an abundant supply of cheap labour. In areas of less rainfall particularly in Punjab and Haryana, it is grown with the help of irrigation.
Rice in India is sown in three ways:

1. Broadcasting,
2. Ploughing or drilling, and
3. Transplanting.

Due to increased use of High Yielding Variety (HYV) seeds (CR Dhan 205, AR Dhan 306, CRR 451 etc.), many of the indigenous varieties were disappeared. In 2016, the first 10 leading rice-producing states are West Bengal (First in India) Uttar Pradesh, Punjab, Tamil Nadu, Andhra Pradesh, Bihar, Chhattisgarh, Odisha, Assam, and Haryana.

Wheat:
Wheat is a temperate crop. Its cultivation is mainly confined to the northwestern part of India. India produces both winter wheat and spring wheat. It is the second most important food crop of the country, after rice.

It requires 10-15°C at the time of sowing and 20-25°C at the time of ripening of grains. Over 85% of India’s wheat production comes from 5 states namely Uttar Pradesh, Punjab, Haryana, Rajasthan and Madhya Pradesh. Apart from these regions, the black soil tract of the Deccan covering parts of Maharashtra and Gujarat also contribute a major wheat production.

IX. HOTS Questions

Question 1.
Can you imagine a world without agriculture?
Answer:
Agriculture is the art and science of cultivating the soil, growing crops and raising livestock. It includes the preparation of plant and animal products for people to use and their distribution to markets.

Agriculture provides most of the world’s food and fabrics. Cotton, wool and leather are all agricultural products. It also provides wood for construction and paper products.

A world without agriculture would be very different compared to the world we live in today. It is easy for us as humans to take for granted things when we don’t really know how they are grown or produced. Without agriculture, we may not get food and clothing. Without timber, we may not be able to build houses and furniture. We may also be deprived of some everyday-products like soap, paper and ethanol, which are made up of some sort of agricultural by-product. Modern medicine also depends on agriculture. Without agriculture, we wouldn’t be here. We must always be thankful for this industry and for those involved in the various activities related to it.

Question 2.
Can you give solutions for the prevailing water disputes in South India (construction of dams / raising of dams / cleaning of tanks}?
Answer:

1. Construction of check dams: In order to prevent surface run off water • during heavy rains. Check dams has to be constructed to regulate the flow of water.
2. Raising of dams: Improves the storage capacity, Strengthening the dams is a must.
3. Cleaning of tanks: Preventing encroachment by strict legal action, desilting the tanks and deepening it in the local areas will provide water supply to the locality, as well as to maintain the areas of ground water level cleaning of tanks is a must

X. Map exercise

Question 1.
Demarcate the major tracts of alluvial soils.
Answer:

Question 2.
Delineate the main regions of black soil.
Answer:

Question 3.
Locate the Hirakud dam, Mettur dam and Damodar dam.
Answer:

Question 4.
Shade the regions of jute cultivation.
Answer:

Question 5.
Mark any three tea and coffee growing areas.
Answer:

Question 6.
Demarcate the regions of desert soil.
Answer:

Question 7.
Locate the fishing hubs: Tuticorin, Chennai,Cochin, Mumbai, Machiiipatnam
Answer:

Question 8.
Demarcate: Cauvery delta, Godavari delta.
Answer:

TB. PNo: 115
Activity 1:

Question 1.
Soil Texture (sand, silt, clay) influence on some properties of soils including water holding capacity. Find out water holding capacity of soils which given above based on following table.
Answer:

TB. PNo: 131
Activity 2:

Question 1.
Complete the following table by your day to day life experience.

Answer:

Samacheer Kalvi 10th Social Science Components of Agriculture Additional Important Questions and Answers

I. Choose the correct answer

Question 1.
……………… soil is formed by the process of leaching.
(a) Alluvial
(b) Black
(c) Laterite
(d) Arid
Answer:
(c) Laterite

Question 2.
Cotton is a ………
(a) food crop
(b) cash crop
(c) dry crop
Answer:
(b) cash crop

Question 3.
……………… is one of the method of soil conservation.
(a) Deforestation
(b) Irrigation
(c) Water logging
(d) Afforestation
Answer:
(d) Afforestation

Question 4.
The “rice bowl of Tamil nadu” is ………..
(a) Madurai
(b) Chennai
(c) Thanjavur
Answer:
(c) Thanjavur

Question 5
……………… are useful for the diversion of flood water from the rivers during rainy season.
(a) Perennial canals
(b) Inundation canals
(c) Open wells
(d) Tube wells
Answer:
(b) Inundation canals

Question 6
The type of fanning which is practised in Punjab and Haryana is ………
(a) subsistence farming
(b) commercial farming
(c) wet farming
Answer:
(b) commercial farming

Question 7.
……………… project is constructed on the river Kaveri in TamilNadu.
(a) Tehri Dam
(b) Kosi Dam
(c) Mettur Dam
(d) Horakud Dam
Answer:
(c) Mettur Dam

Question 8.
In the regions with abundant rainfall ……. is grown.
(a) millet
(b) wheat
(c) rice
Answer:
(c) rice

Question 9.
The traditional farming method that results in low productivity is:
(a) mixed farming
(b) shifting agriculture
(c) intensive farming
(d) subsistence farming
Answer:
(d) subsistence farming

Question 10.
One of the important zaid crops is ………….
(a) rice
(b) wheat
(c) watermelon
Answer:
(c) watermelon

Question 11.
First Live-stock census was conducted in India in the year:
(a) 1819
(b) 1919
(c) 1618
(d) 1981
Answer:
(b) 1919

Question 12.
The National Research Center on Plant Biotechnology was established in ………
(a) 1985
(b) 1980
(c) 1990
Answer:
(a) 1985

II. Consider the given statements and choose the right option given below

Question 1.
Assertion (A): Indian agriculture is largely dominated by food crops. Reason (R): India has a large population.
(a) Both (A) and (R) are true and (R) explains (A)
(b) Both (A) and (R)are true: (R) does not explain (A)
(c) (A) is correct (R) is false
(d) (A) is false (R) is true
Answer:
(c) (A) is correct (R) is false

Question 2.
Assertion (A): Forest and mountain soils differ from region to region. Reason (R): Due to the absence of vegetative cover.
(a) Both (A) and (R) are true and (R) explains (A)
(b) Both (A) and (R)are true: (R) does not explain (A)
(c) (A) is correct (R) is false
(d) (A) is false (R) is true
Answer:
(c) (A) is correct (R) is false
Hint: Reason is due to mechanical weathering caused by snow, rain, temperature variation depending on climate.

Question 3.
Assertion (A): Terrace farming method is practiced on hill and mountain slopes. Reason (R): The availability of land is limited and it checks soil erosion.
(a) Both (A) and (R) are true and (R) explains (A)
(b) Both (A) and (R)are true: (R) does not explain (A)
(c) (A) is correct (R) is false
(d) (A) is false (R) is true
Answer:
(a) Both (A) and (R) are true and (R) explains (A)

Question 4.
Assertion (A): Pulses are usually rotated with other crops.
Reason (R): They are used as human food and feeding cattle.
(a) Both (A) and (R) are true and (R) explains (A)
(b) Both (A) and (R) are true and (R) does not explain (A)
(c) (A) is correct (R) is false
(d) (A) is false (R) is true
Answer:
(c) (A) is correct (R) is false
Hint: They are mostly leguminous in nature and fixes atmospheric nitrogen helps soil to regain its fertility.

III. Pick the odd one out

1. (a) Tea, (b) Sugarcane, (c) Cotton, (d) Ragi
2. (a) Khandsari, (b) Herrings, (c) Mackerels, (d) Eels
3. (a) Damodhar, (b) Mahanadi, (c) Kaveri, (d) Raingun
4. (a) Water wheel, (b) Sprinkler, (c) Open well, (d) poly house
5. (a) Blue Revolution, (b) soil erosion, (c) Green Revolution, (d) Soil erosion
6. (a) Fishing, (b) Kharif, (c) Rabi, (d) Zaid

Answer:

1. (d) Ragi
2. (a) Khandsari
3. (d) Raingun
4. (c) Open well
5. (d) Soil erosion
6. (a) Fishing

IV. Match the following

Question 1.
Match the Column I with Column II.

Answer:
A. (v)
B. (i)
C. (ii)
D. (iii)
E. (iv)

Question 2.
Match the Column I with Column II.

Answer:
A. (ii)
B. (iv)
C. (v)
D. (i)
E. (iii)

Question 3.
Match the Column I with Column II.

Answer:
A. (vi)
B. (iii)
C. (ii)
D. (i)
E. (iv)
F. (v)

V. Answer in brief

Question 1.
Why is tank irrigation more prevalent in South India than North India?
Answer:
The undulated topography of peninsular region forms large depressions to collect water which become tanks. So the tank irrigation is more prevalent in South India than North India.

Question 2.
How laterite soils are formed?
Answer:
Laterite soils are formed in the regions where alternate wet and dry conditions prevail.
It is formed by the process of leaching.

Question 3.
Which is an acute problem in India? How?
Answer:
Soil degradation is an acute problem in India. According to a 2015 report of the Indian institute of remote sensing (IIRS). The estimated the amount of soil .erosion that occurred in India was 147 million hectares.
The main problems of the Indian soils are

1. Soil erosion
2. Degradation of Soil
3. Water-logging
4. Saline and Alkaline and
5. Salt Flats.

Question 4.
Draw a flow chart showing the sources of irrigation and their classification.
Answer:

Question 5.
Write few lines about Rain Gun.
Answer:
It is used to spread water like rain and used to serve for crops which used to grow up to 4 feet or high also but we have to adjust sprinklers height as per crop size, typical usage of Rain guns are in sugarcane, maize crops.

Question 6.
Name the food crops grown in India.
Answer:
Food crops that are grown in India include cereals and pulses amongst which rice, wheat, jowar, bajra, maize, barely, ragi, gram and tur are important.

Question 7.
Give short notes about Terrace cultivation.
Answer:
This is practised especially in hilly areas, where lands are of sloping nature. The hill and mountains slopes are cut to form terraces and the land is used in the same way as in permanent agriculture.

Question 8.
Name the five leading states that contribute 85% of India’s wheat production.
Answer:
Uttar Pradesh, Punjab, Haryana, Rajasthan and Madhya Pradesh are the leading states in wheat production in India.

Question 9.
What are the products of Sugarcane?
Answer:
Sugarcane provides raw material for the sugar industry. Besides providing sugar, gur and Khandsari it supplies molasses for alcohol industry and bagasse for paper industry.

Question 10.
How jute is useful for trade?
Answer:

1. Jute fibre provides raw material for Jute industry.
2. It is used for manufactruing of gunny bags, carpets, hessian, ropes and strings, rugs, clothes, tarpaulins, upholstery etc.

Question 11.
What is the other name of ‘Shifting Agriculture1? Who practice shifting agriculture? and how it is called in different regions?
Answer:
‘Shifting Agriculture’ is also called as ‘Slash and bum’ Agriculture. The tribal people follow this type of agriculture. It is called by different names in different regions in India as follows.

Name	Place
Jhum	Assam
Poonam	Kerala
Podu	Andhra Pradesh, Odisha
Beewar, Mashan, Penda, Beera	Various parts of Madhya Pradesh

Question 12.
What is dry farming?
Answer:
Dry farming is the type of farming practiced in arid areas where there is lack of irrigation facilities. Crops grown in these areas can withstand dry conditions.

Question 13.
What are called cash crops? Give examples.
Answer:
Crops which are cultivated for commercial purpose are called cash crops, eg: Sugarcane, tobacco, fibre crops and oil seeds.

Question 14.
Which is the largest oil seeds producing state? What is the position of India in oil seeds production in the world?
Answer:
Gujarat is India’s largest oil seeds producing state. India is the second largest producer of oil seeds in the world next to China.

Question 15.
Define Green Revolution.
Answer:
The process of improving and increasing the production of food crops using modem techniques is referred as Green Revolution.

Question 16.
Mention the different breeds of cattle population in India.
Answer:
Cattle population in India belongs to different breeds. They are

1. Milch breed
2. Draught breed
3. Mixed or General breed

VI. Give Reasons

Question 1.
Tank irrigation is popular in peninsular India.
Answer:
The undulating relief, absence of perennial rivers, Impermeable rock structure and natural depression are the reasons for having tank irrigation most popular in Peninsular India.

Question 2.
Why tea is grown on the hill slopes?
Answer:
Tea plants require high rainfall but its roots cannot tolerate water logging. Frost condition is a must for tea plants. So it is grown on the hill slopes.

Question 3.
Inundation canals are not dependable source of irrigation.
Answer:
Inundation canals are operational only during rainy season for the diversion of flood water directly from the rivers. Hence these canals are not dependable source of irrigation.

Question 4.
Shifting agriculture is also called as slash and burn agriculture.
Answer:
Once the forest land piece is cleared by tribal people they grow crops for two to three years and bum the stumps after harvest and abandoning the lands to regain its fertility and then move to new areas. Thus, shifting agriculture is also called ‘slash and bum’ agriculture.

Question 5.
Only little surplus is left in subsistence farming.
Answer:
Mainly in subsistence farming crops are grown for family consumption leaving little surplus to sell in the market. Preference will be given to food crops as per their needs.

Question 6.
Indian agriculture is mainly dominated by the food crops.
Answer:
As the population increases the need for food also increase. Due to the need and to supply to the large population Indian agriculture is mainly dominated by the food crops.

VII. Distinguish between the following

Question 1.
Laterite and Red soil.
Solution:
Laterite soil:

1. Femed by the process of leaching under wet and hot dry conditions.
2. Mainly composed of hydrated oxides of iron and aluminium.
3. Found mostly on hilly areas.
4. Suitable for tea, coffee, rubber and cashewnut.

Red soil:

1. Formed by the decomposition of ancient crystalline rocks.
2. Rich in minerals like iron and magnesium.
3. Found in plateau regions.
4. Suitable for pulses and sugarcane.

Question 2.
Arid and desert soil and Peaty and marshy soil.
Answer:
Arid and Desert soil:

1. Formed due to dry climate and high temperature.
2. Poor in organic matter and nitrogen rich in salt content.
3. Found in Rajasthan Northern Gujarat and Southern Punjab.
4. Millets, barley and pulses grow with irrigation.

Peaty and Marshy soil:

1. Formed in humid regions from organic matter.
2. Poor in potash and phosphate rich in vegetable organic matter.
3. Found in coastal areas and Sunderban Deltaic region, Kerala, Odisha, West Bengal.
4. Ideal for paddy and Jute cultivation.

Question 3.
Open well and Tube well irrigation.
Answer:
Open well irrigation:

1. Need sufficient ground water availability.
2. Practiced in areas of Ganga plains and river Deltaic regions.

Tube well irrigation:

1. Can be found in areas of low water table and soft geological subsurface.
2. Need sufficient water supply. Predominant in the states of Gujarat, Maharashtra, Madhya Pradesh and TamilNadu.

Question 4.
Bhakra Nangal and Hirakud project.
Answer:
Bhakra Nangal Project:

1. Constructed on the river Sutlej.
2. Highest gravity dam in the world.
3. Punjab, Haryana and Rajasthan states are benefitted.

Hirakud Project:

1. Constructed on the river Mahanadhi.
2. Longest dam in the world.
3. State of Odhisha is benefitted by this project.

Question 5.
Subsistence and Mixed farming.
Answer:
Subsistence farming:

1. Crops is mainly cultivated for family consumption.
2. Traditional farming methods are used due to small land holdings.
3. Mainly concentrated on food crops.

Mixed farming:

1. Integrated farming to satisfy many needs of the farmers.
2. Modem techniques is used for crop cultivation done in a vast area.
3. System include crop production along with raising live stock, poultry, fisheries, bee keeping etc.

Question 6.
Food and Cash crops.
Answer:
Food crops:

1. Mainly grown for consumption purpose.
2. Food crops include rice, wheat, pulses etc.
3. Apart from consumption used as raw materials for agro based industries.

Cash crops:

1. Crops are cultivated for commercial purpose.
2. Sugarcane, cotton, jute, oil seeds are the main cash crops. .
3. Mainly produced for raw materials for industries and earn valuable foreign exchange.

Question 7.
Rice and Wheat.
Answer:
Rice:

1. Mainly Tropical crop.
2. Need abundant supply of water till harvest.
3. West Bengal, Uttar Pradesh, Punjab, TamilNadu, Andhra Pradesh are some of the leading states in Rice production.

Wheat:

1. Sub tropical or Temperate crop.
2. Need moderate water supply.
3. Uttar Pradesh, Punjab, Haryana, Rajasthan and Madhya Pradesh are the leading states in wheat production.

VIII. Answer in a paragraph

Question 1.
What is a multipurpose project and explain its purpose?
Answer:
A comprehensive river valley project which serves a number of purposes simultaneously is called a “Multipurpose project”. Multipurpose projects serve the following purposes.

1. They help to store water, that can be utilised, when water, is in great demand both for agricultural and domestic purpose.
2. They check floods and famines.
3. Afforestation is undertaken in the catchment areas of river, which helps conservation of water, soil and wildlife. Thus it keeps ecosystem intact.
4. Production of hydro electricity is also another purpose of these projects. It is a pollution free of energy and is renewable energy.
5. They attract tourists and develops tourism industry.
6. Soil conservation and land relamation are other purpose of these projects.

Question 2.
What do you mean by Irrigation? Why it is necessary in India?
Answer:

1. Watering to agricultural lands by artificial means for cultivation is called Irrigation.
2. India is a tropical monsoon country.
3. 75% of rainfall is received within a span of four months.
4. Indian rainfall from monsoons are seasonal, uneven, irregular and erratic in nature.
5. So always there is a need for irrigation to carry out agricultural activities during dry period.
6. Besides erratic rainfall prevalence of high temperature, cultivation of annual crops and hydrophytes.
7. Commercial farming and porous soil make irrigation an essential one for agriculture in India.

Question 3.
What are the different sources of irrigation used in different parts of India?
Answer:
The main sources of irrigations are
1. Canal irrigation
2. Well irrigation
3. Tank irrigation

1. Canal irrigation:
It is the second most important sources of irrigation in India. The Canals are of two types.
i. Inundation canals
ii. Perennial canals

i. Inundation canals:
In this, water is taken directly from the rivers without making any kind of barrage or dam. Such canals are useful for the diversion of flood water from the rivers and remains operational during rainy season.

ii. Perennial canals:
These are developed from perennial work by constructing barrage to regulate the flow of water. These canals are useful for irrigation.

2. Well irrigation:
A Well is a hole or trough usually vertical excavated in the earth for brining groundwater to the surface. It contributes about 62% of net irrigated area in India. Wells are of two types.
i. Open well
ii. Tube well

i. Open well:
This type of irrigation is widely practiced in the areas where groundwater is sufficiently available. The areas are in Ganga plains, the deltaic region of Mahanadi, Godavari, Krishna, Cauvery and parts of Narmada and Tapti valleys.

ii. Tube well:
Tube wells are developed in the areas of low water table, sufficient power supply and soft subsurface geological units. Tube wells are predominant in the states of Gujarat, Maharashtra, Punjab, MP, and Tamil Nadu.

3. Tank irrigation:
A tank is a natural or man-made hollow on the surface developed by constructing a small bund around it across a stream It is used to collect and store water for irrigation and other purpose. It also includes irrigation from taken and ponds.

Question 4.
How is Live-stock census conducted in TamilNadu?
Answer:
State Government is conducting Live stock census with the help of:

1. Department of Animal Husbandary at State level and
2. Regional Joint Director at District level under the guidelines of Government of India ministry of Agriculture and farmers welfare,
3. Department of Animal husbandary, Dairying and Fisheries conducted once in 5 years.

Question 5.
Explain about the major issues faced by the Indian farmers?
Answer:
We can divide the problems faced by the Indian agriculture and by the farmers into two Natural and Man made.
Natural problems:

1. Soil erosion: Large tracts of land suffer from soil erosion by wind and water.
2. Infertile soil: Growing crops for many years without replenishing led to the exhaution of soil and its depletion.
3. Lack of Irrigation: Only some areas of the cropped falls under irrigation.

Man made problems:

1. Small land holdings and fragmented land: Poor status made the farmers to have small land and also some farmers possesses share from their ancestral property cannot afford to apply mechanism.
2. High costs of Inputs: Good quality of seeds are out of reach for many small and marginal farmers due to their high price.
3. Agricultural marketing: Absence of sound marketing, facility, interference of local traders and middlemen for the disposal of their produce, fluctuations in the price.
4. In adequate transport: Lakhs of villages are not w7ell connected with main roads or with market centres. Lack of cheap and efficient means of transportation is not available.
5. Scarcity of capital: Huge capital is needed to purchase advanced farm machineries and equipments which the poor farmers cannot afford to buy.

Question 6.
List out some of the Agricultural Revolutions in India.
Answer:

Question 7.
“Per Drop more Crop”. Explain this statement.
Answer:

1. It is the scheme introduced by the Government of India with the objective to enhance water use efficiency.
2. This micro irrigation scheme comes under “Pradhan Mantri Krishi Sinchayee Yojana (PMKSY) and centrally sponsored scheme on micro irrigation.
3. It promotes appropriate technological interventions like drop and sprinkler irrigation technologies in agriculture and encourage farmers to use water saving and conservation technique.
4. Following five states progressed 78% under micro irrigation scheme
   • Andhra Pradesh
   • Karnataka
   • Gujarat
   • Maharashtra
   • TamilNadu

IX. Map Questions
Mark the following on the outline map of India.

Question 1.
Areas of Red soil and Mountain soil.
Answer:

Question 2.
Demarcate the states producing the highest for the following crops.
Answer:
(i) Paddy

(ii) Sugarcane

(iii) Cotton

(iv) Wheat

Question 3.
Kosi project, Tungabadra, Periyar Dam, Nagarjuna Sagar.
Answer:

Students can download 10th Science Chapter 11 Carbon and its Compounds Questions and Answers, Notes, Samacheer Kalvi 10th Science Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

Tamilnadu Samacheer Kalvi 10th Science Solutions Chapter 11 Carbon and its Compounds

Samacheer Kalvi 10th Science Carbon and its Compounds Text Book Back Questions and Answers

I. Choose the best answer:

Question 1.
The molecular formula of an open-chain organic compound is C₃H₆. The class of the compound is:
(a) alkane
(b) alkene
(c) alkyne
(d) alcohol
Answer:
(b) alkene

Question 2.
The IUPAC name of an organic compound is 3-Methyl butan-1-ol. What type of compound it is?
(a) Aldehyde
(b) Carboxylic acid
(c) Ketone
(d) Alcohol
Answer:
(d) Alcohol

Question 3.
The secondary suffix used in IUPAC nomenclature of an aldehyde is:
(a) – ol
(b) – oic acid
(c) – al
(d) – one
Answer:
(c) – al

Question 4.
Which of the following pairs can be the successive members of a homologous series?
(a) C₃H₈ and C₄H₁₀
(b) C₂H₂ and C₂H₄
(c) CH₄ and C₃H₆
(d) C₂H₅OH and C₄H₈OH.
Answer:
(a) C₃H₈ and C₄H₁₀
Hint: Two successive members of a homologous series must have a difference of -CH₂ in the molecular formula.
\(\mathrm{C}_{3} \mathrm{H}_{8} \stackrel{+\mathrm{CH}_{2}}{\longrightarrow} \mathrm{C}_{4} \mathrm{H}_{10}\).

Question 5.
C₂H₅OH + 3O₂ → 2CO₂ + 3H₂O is a:
(a) Reduction of ethanol
(b) Combustion of ethanol
(c) Oxidation of ethanoic acid
(d) Oxidation of ethanal
Answer:
(b) Combustion of ethanol

Question 6.
Rectified spirit is an aqueous solution which contains about ______ of ethanol.
(a) 95.5 %
(b) 75.5 %
(c) 55.5 %
(d) 45.5 %.
Answer:
(a) 95.5 %
Rectified spirit is a mixture of 95.5 % of ethanol and 4.5 % of water.

Question 7.
Which of the following are used as anaesthetics?
(a) Carboxylic acids
(b) Ethers
(c) Esters
(d) Aldehydes
Answer:
(b) Ethers

Question 8.
TFM in soaps represents _____ content in soap.
(a) mineral
(b) vitamin
(c) fatty acid
(d) carbohydrate.
Answer:
(c) fatty acid
Hint: TFM – Total Fatty Matter. It corresponds the fatty acid (oil).

Question 9.
Which of the following statements is wrong about detergents?
(a) It is a sodium salt of long chain fatty acids
(b) It is sodium salts of sulphonic acids
(c) The ionic part in a detergent is – SO₃ ^–Na⁺
(d) It is effective even in hard water.
Answer:
(a) It is a sodium salt of long-chain fatty acids

II. Fill in the blanks:

1. An atom or a group of atoms which is responsible for chemical characteristics of an organic compound is called …………
2. The general molecular formula of alkynes is ………..
3. In IUPAC name, the carbon skeleton of a compound is represented by ………. (root word / prefix / suffix)
4. (Saturated / Unsaturated) ……….. compounds decolourize bromine water.
5. Dehydration of ethanol by cone. Sulphuric acid forms ………. (ethene/ ethane)
6. 100 % pure ethanol is called ………..
7. Ethanoic acid turns ………… litmus to …………
8. The alkaline hydrolysis of fatty acids is termed as …………
9. Biodegradable detergents are made of …………. (branched / straight) chain hydrocarbons.
Answer:
1. Functional group
2- C_nH_2n-2
3. root word
4. unsaturated
5. ethene
6. absolute alcohol
7. Blue, red
8. Saponification
9. straight

III Match the following:

Question 1.
Match the Column I and Column II.

Answer:
A. (iii)
B. (iv)
C. (v)
D. (ii)
E. (i)

IV. Assertion and Reason:

Answer the following questions using the data given below:
Question 1.
Assertion: Detergents are more effective cleansing agents than soaps in hard water.
Reason: Calcium and magnesium salts of detergents are water soluble.
(a) Assertion and Reason are correct, Reason explains the Assertion.
(b) Assertion is correct, Reason is wrong.
(c) Assertion is wrong, Reason is correct.
(d) Assertion and Reason are correct, Reason doesn’t explains Assertion.
Answer:
(a) Assertion and Reason are correct, Reason explains the Assertion.

Question 2.
Assertion: Alkanes are saturated hydrocrabons.
Reason: Hydrocarbons consits of covalnet bonds.
(a) Assertion and Reason are correct, Reason explains the Assertion .
(b) Assertion is correct, Reason is wrong.
(c) Assertion is wrong, Reason is correct.
(d) Assertion and Reason are correct, Reason doesn’t explains Assertion.
Answer:
(d) Assertion and Reason are correct, Reason doesn’t explains Assertion.

V. Short answer questions:

Question 1.
Name the simplest ketone and give its structural formula.
Answer:
The simplest ketone is Propanone.
It’s structural formula:

Question 2.
Classify the following compounds based on the pattern of carbon chain and give their structural formula:
(i) Propane
(ii) Benzene
(iii) Cyclo butane
(iv) Furan.
Answer:

Question 3.
How is ethanoic acid prepared from ethanol? Give the chemical equation.
Answer:
Ethanol is oxidized to ethanoic acid with alkaline KMnO₄ or acidified K₂Cr₂O₇.

Question 4.
How do detergents cause water pollution? Suggest remedial measures to prevent this pollution?
Answer:

• Some detergents having a branched hydrocarbon chain are not fully biodegradable by microorganisms present in water. So, they cause water pollution.
• They have straight hydrocarbon chains, in biodegradable detergents, which can be easily degraded by bacteria.

Question 5.
Differentiate soaps and detergents.
Answer:

VI. Long answer questions.

Question 1.
What is called a homologous series? Give any three of its characteristics?
Answer:
A homologous series is a group or a class of organic compounds having the same general formula and similar chemical properties in which the successive members differ by a – CH₂ group.
Characteristics of homologous series:

• All members of a homologous series contain the same elements and functional group.
• All members of a homologous series can be prepared by a common method.
• Chemical properties of the members of a homologous series are similar.

Question 2.
Arrive at, systematically, the IUPAC name of the compound: CH₃-CH₂– CH₂-OH.
Answer:
Step 1: The parent chain consists of 3 carbon atoms. The root word is ‘Prop’.
Step 2: There are single bonds between the carbon atoms of the chain. So, the primary suffix is ‘ane’.
Step 3: Since, the compound contains – OH group, it is an alcohol. The carbon chain is numbered from the end which is closest to – OH group. (Rule 3)

Step 4: The locant number of – OH group is l and thus the secondary suffix is ‘l-ol’.
The name of the compound is Prop + ane + (l – ol) = Propan-l-ol

Question 3.
How is ethanol manufactured from sugarcane?
Answer:
Ethanol is manufactured in industries by the fermentation of molasses, which is a by-product obtained during the manufacture of sugar from sugarcane. Molasses is a dark coloured syrupy liquid left after the crystallization of sugar from the concentrated sugarcane juice. Molasses contain about 30% of sucrose, which cannot be separated by crystallization. It is converted into ethanol by the following steps:
(i) Dilution of molasses : Molasses is first diluted with water to bring down the concentration of sugar to about 8 to 10 percent.

(ii) Addition of Nitrogen source : Molasses usually contains enough nitrogenous matter to act as food for yeast during the fermentation process. If the nitrogen content of the molasses is poor, it may be fortified by the addition of ammonium sulphate or ammonium phosphate.

(iii) Addition of YeastrThe solution obtained in step (ii) is collected in large ‘fermentation tanks’ and yeast is added to it. The mixture is kept at about 303K for a few days. During this period, the enzymes invertase and zymase present in yeast, bring about the conversion of sucrose into ethanol.

The fermented liquid is technically called wash.

(iv) Distillation of ‘Wash’: The fermented liquid (i.e., wash), containing 15 to 18 percent alcohol, is now subjected to fractional distillation. The main fraction drawn is an aqueous solution of ethanol which contains 95.5% of ethanol and 4.5% of water. This is called rectified spirit. This mixture is then refluxed over quicklime for about 5 to 6 hours and then allowed to stand for 12 hours. On distillation of this mixture, pure alcohol (100%) is obtained. This is called absolute alcohol.

Question 4.
Give the balanced chemical equation of the following reactions:
(i) Neutralization of NaOH with ethanoic acid.
Answer:

(ii) Evolution of carbon dioxide by the action of ethanoic acid with NaHCO₃.
Answer:

(iii) Oxidation of ethanol by acidified potassium dichromate.
Answer:

(iv) Combustion of ethanol.
Answer:

Question 5.
Explain the mechanism of cleansing action of soap.
Answer:
A soap molecule contains two chemically distinct parts that interact differently with water. It has one polar end, which is a short head with a carboxylate group (-COONa) and one non – polar end having the long tail made of the hydrocarbon chain.

The polar end is hydrophilic (Water-loving) in nature and this end is attracted towards the water. The non – polar end is hydrophobic (Water hating) in nature and it is attracted towards dirt or oil on the cloth, but not attracted towards the water. Thus, the hydrophobic part of the soap molecule traps the dirt and the hydrophilic part makes the entire molecule soluble in water.

When soap or detergent is dissolved in water, the molecules join together as clusters called ‘micelles’. Their long hydrocarbon chains attach themselves to the oil and dirt. The dirt is thus surrounded by the non-polar end of the soap molecules. The charged carboxylate end of the soap molecules makes the micelles soluble in water. Thus, the dirt is washed away with the soap.

VII. Hot Questions.

Question 1.
The molecular formula of an alcohol is C₄H₁₀O. The locant number of its -OH group is 2.
(i) Draw its structural formula.
Answer:

(ii) Give its IUPAC name.
Answer:
Butan-2-ol

(iii) Is it saturated or unsaturated?
Answer:
Saturated

Question 2.
An organic compound ‘A’ is widely used as a preservative and has the molecular formula C₂H₄O₂. This compound reacts with ethanol to form a sweet smelling compound ‘B’.
(i) Identify the compound ‘A’.
Answer:
Organic Compound ‘A’ with the molecules formula C₂ H₄ O₂ which is a preservative is acetic acid (or) ethanoic acid.
A – CH₃COOH

(ii) Write the chemical equation for its reaction with ethanol to form compound ‘B’.
Answer:

B – Ethyl ethanoate (ester – sweet smelling)

(iii) Name the process.
Answer:
Esterification

Samacheer Kalvi 10th Science Carbon and its Compounds Additional Important Questions and Answers

I. Choose the best answer.

Question 1.
The general formula of alkane series is:
(a) C_nH_2n
(b) C_nH_2n-1
(C) C_nH_2n+2
(d) C_nH_2n-2
Answer:
(C) C_nH_2n+2

Question 2.
Organic compounds are _____ in nature.
(a) flammable
(b) inflammable
(c) heavy
(d) light.
Answer:
(b) inflammable

Question 3.
The Heterocyclic compound is:
(a) Benzene
(b) Pyridine
(c) Naphthalene
(d) Camphor
Answer:
(b) Pyridine

Question 4.
Pick out the unsaturated compound from the following ______.
(a) CH₃ – CH₂ – CH₃
(b) CH₃ – CH = CH₂
(c) \(\mathrm{CH}_{3}-\mathrm{C} \equiv \mathrm{CH}\)
(d) both (b) and (c).
Answer:
(d) both (b) and (c).

Question 5.
……….. will decolourise Br₂/H₂O.
(a) Methane
(b) Pent-2-ene
(c) Ethyl alcohol
(d) Ethanal
Answer:
(b) Pent-2-ene

Question 6.
The simplest alkane is ______.
(a) Ethane
(b) Ethyne
(c) Propane
(d) Methane.
Answer:
(d) Methane.

Question 7.
……….. is the prefix used for -NH₂ Group.
(a) Fluoro
(b) Methyl
(c) Amino
(d) Nitro
Answer:
(c) Amino

Question 8.
The IUPAC name of an organic compound is Pentan-2-one. The secondary suffix is:
(a) Pentan
(b) an
(c) -one
(d) -2-
Answer:
(c) -one

Question 9.
Molasses is fortified with ………… to increase the nitrogen content.
(a) (NH₄)₂SO₄ (or) (NH₄)₃PO₄
(b) (NH₄)₂CO₃ (or) NH₄Cl
(c) (NH₄)₂CO₃ (or) NH₄OH
(d) None of the above
Answer:
(a) (NH₄)₂SO₄ (or) (NH₄)₃PO₄

Question 10.
Which one of the following is a general formula for alkyne?
(a) C_nH_2n
(b) C_nH_2n+2
(c) C_nH_2n-2
(d) C_nH_n
Answer:
(c) C_nH_2n-2

II. Fill in the blanks.

1. The common difference between the successive member of the homologous series if ……….. group.
2. Denatured spirit is a mixture of ethanol and …………
3. Methane gas is produced when the sodium salt of ethanoic acid is ………… with soda lime.
4. For coagulating rubber from latex ………… is used.
5. ………… is added to prevent the caking of the detergent powder.
6. When a soap or detergent is added to water the moleculer cluster together to form ……….
7. The terminal functional group among aldehydes and ketones is ………..
8. On dehydrogenation of ethanol with Cu/573 K it gives ………… gas.
9. ……… converts glucose into ethanol and carbondi-oxide.
10. The structural formula of Pentanoic acid is …………
Answer:
1. -CH₂
2. pyridine
3. decarboxylated
4. ethanoic acid
5. Na₂SO₄ or Sodium sulphate
6. micelles
7. aldehyde
8. H₂
9. Zymase
10. CH₃CH₂CH₂CH₂COOH

III Match the following:

Question 1.
Match the column I and column II.

Answer:
A. (ii)
B. (iii)
C. (v)
D. (i)
E. (iv)

Question 2.
Match the column I and column II.

Answer:
A. (v)
B. (iv)
C. (i)
D. (iii)
E. (ii)

IV Assertion and Reason.

Answer the following questions using the data given below:
Question 1.
Assertion: Alkynes decolourise bromine water.
Reason: Alkynes are unsaturated compounds.
(a) Assertion and Reason are correct, Reason explains Assertion.
(b) Assertion is correct, Reason is wrong.
(c) Assertion is wrong, Reason is correct.
(d) Assertion and Reason are correct, Reason doesn’t explains Assertion.
Answer:
(a) Assertion and Reason are correct, Reason explains Assertion.

Question 2.
Assertion: Denaturation of ethanol makes it unfit for drinking purpose.
Reason: Ethanol is mixed with Pyridine for denaturation.
(a) Assertion and Reason are correct, Reason explains Assertion.
(b) Assertion is correct, Reason is wrong.
(c) Assertion is wrong, Reason is correct.
(d) Assertion and Reason are correct, Reason doesn’t explains Assertion.
Answer:
(a) Assertion and Reason are correct, Reason explains Assertion.

Question 3.
Assertion: Organic compounds contains covalent bond.
Reason: Organic compounds have low melting and boiling points.
(a) Assertion and Reason are correct, Reason explains Assertion.
(b) Assertion is correct, Reason is wrong.
(c) Assertion is wrong, Reason is correct.
(d) Assertion and Reason are correct, Reason doesn’t explains Assertion.
Answer:
(d) Assertion and Reason are correct, Reason doesn’t explains Assertion.

Question 4.
Assertion: Due to catenation a large number of carbon compounds are formed.
Reason: Carbon compounds show the property of allotropy.
(a) Assertion and Reason are correct, Reason explains Assertion.
(b) Assertion is correct, Reason is wrong.
(c) Assertion is wrong, Reason is correct.
(d) Assertion and Reason are correct, Reason doesn’t explains Assertion.
Answer:
(b) Assertion is correct, Reason is wrong.

V. Short answer questions:

Question 1.
Define isomerism with an example.
Answer:
Isomerism is a phenomenon in which organic compounds having the same molecular formula will have different structural formula.
Eg: for the molecular formula C₂H₆O we can write
CH₃CH₂OH – ethanol
CH₄O CH₃ – Methoxy methane

Question 2.
What are root words?
Answer:
Root words are the basic unit which describes the carbon skeleton. It gives the number of carbon atoms present in the parent chain of the compound and the pattern of their arrangement.

Question 3.
Write The functional group and the secondary suffix of the following compounds.
Answer:

Question 4.
What happens when ethanol is dehydrated with con.H₂SO₄ at 443K?
Answer:
Dehydration (Loss of water): When ethanol is heated with cone. H₂SO₄ at 443K, it loses a water molecule i.e., dehydrated to form ethene.

Question 5.
Write a note on esterification.
Answer:
The reaction of an alcohol with a carboxylic acid gives a compound having fruity odour. This compound is called an ester and the reaction is called esterification. Ethanol reacts with ethanoic acid in the presence of cone. H₂SO₄ to form ethyl ethanoate, an ester.

Question 6.
Write tests to identify the presence of ethanoic acid.
Answer:

1. Ethanoic acid turns blue litmus paper to red.
2. Ethanoic acid gives brisk effervescence when treated with Na₂CO₃
3. Ethanoic acid gives a sweet-smelling compound called ester when treated with ethanol.

Question 7.
Write a note on decarboxylation reaction.
Answer:
Decarboxylation (Removal of CO₂): When a sodium salt of ethanoic acid is heated with soda lime (solid mixure of 3 parts of NaOH and 1 part of CaO), methane gas is formed.

Question 8.
What is hard soap?
Answer:
Soaps, which are prepared by the saponification of oils or fats with caustic soda (sodium hydroxide), are known as hard soaps. They are usually used for washing purposes.

Question 9.
Why ordinary soap is not suitable for using with hard water?
Answer:
Ordinary soaps when treated with hard water, precipitate as salts of calcium and magnesium. They appear at the surface of the cloth as sticky grey scum. Thus, the soaps cannot be used conveniently in hard water.

Question 10.
What are the advantages of detergents over soaps?
Answer:
Detergents are better than soaps because of they:

1. can be used in both hard and soft water and can clean more effectively in hard water than soap.
2. can also be used in saline and acidic water.
3. do not leave any soap scum on the tub or clothes.
4. dissolve freely even in cool water and rinse freely in hard water.
5. can be used for washing woollen garments, whereas soap cannot be used.
6. have a linear hydrocarbon chain, which is biodegradable.
7. are active emulsifiers of motor grease.
8. do an effective and safe cleaning, keeping even synthetic fabrics brighter and whiter.

VI. Long answer questions.

Question 1.
Write the IUPAC name of the following compounds
Answer:

Question 2.
Write the characteristics of organic compounds.
Answer:

1. Organic compounds have a high molecular weight and a complex structure.
2. They are mostly insoluble in water but soluble in organic solvents such as ether, carbon tetrachloride, toluene, etc.
3. They are highly inflammable in nature.
4. Organic compounds are less reactive compared to inorganic compounds. Hence, the reactions involving organic compounds proceed at slower rates.
5. Mostly organic compounds form covalent bonds in nature.
6. They have a lower melting point and boiling point when compared to inorganic compounds
7. They exhibit the phenomenon of isomerism, in which a single molecular formula represents several organic compounds that differ in their physical and chemical properties
8. They are volatile in nature.
9. Organic compounds can be prepared in the laboratory.

Question 3.
List the advantages of detergents over soaps.
Answer:

1. Can be used in both hard and soft water and can clean more effectively in hard water than soap.
2. Can also be used in saline and acidic water.
3. Do not leave any soap scum on the tub or clothes.
4. Dissolve freely even in cool water and rinse freely in hard water.
5. Can be used for washing woollen garments, where as soap cannot be used.
6. Have a linear hydrocarbon chain, which is biodegradable.
7. Are active emulsifiers of motor grease.
8. Do an effective and safe cleansing, keeping even synthetic fabrics brighter and whiter.

Question 4.
Draw the schematic diagram for the classification of organic compounds based on the pattern of carbon chain with example.
Answer:

Question 5.
Explain the manufacture of soap.
Answer:
Manufacture of soap by Kettle Process This is the oldest method. But, it is still widely used in the small scale preparation of soap. There are mainly, two steps to be followed in this process.

1. Saponification of oil: The oil, which is used in this process, is taken in an iron tank (kettle). The alkaline solution (10%) is added into the kettle, a little in excess. The mixture is boiled by passing steam through it. The oil gets hydrolysed after several hours of boiling. This process is called Saponification.

2. Salting out of soap: Common salt is then added to the boiling mixture. Soap is finally precipitated in the tank. After several hours the soap rises to the top of the liquid as a ‘curdy mass’. The neat soap is taken off from the top. It is then allowed to cool down.

Question 6.
Ethanol is heated with excess con.H₂SO₄ at 443K.
(a) Name the reaction that occurs and explain it.
Answer:
Dehydration (Loss of water).
When ethanol is heated with conc.H₂SO₄ at 443K, it loses a water molecule i.e., dehydrated to form ethene.

Answer:

(c) What is the product formed? What happen when this gas is passed through Br₂/H₂O.
Answer:
Ethene gas.
When it is passed through Br₂/H₂O it gets decolourised because it is an unsaturated compound.

(d) Why does no decolonization occurs when ethanol is treated with Br₂/H₂O?
Answer:
Ethanol is a saturated compound. Therefore no decolourisation occurs.

VII. Hot Questions.

Question 1.
Organic compounds A and B are isomers with the molecular formula C₂H₆O (A) liberates H2 gas when it reacts with metallic sodium whereas (B) does not. Compound (A) reacts with ethanoic acid and forms a fruity smelling compound (C). Identify A, B and C and explain the reactions.
Answer:
(A) and (B) are compounds with same molecular formula C₂H₆O.
(A) reacts with metallic Na and liberates H₂↑
∴ (A) is ethanol [CH₃CH₂OH]
(B) is methoxy methane [CH₃OCH₃]

(A) reacts with ethanoic acid and forms ester.

(A) Ethanol, CH₃CH₂OH
(B) Methoxy methane, CH₃OCH₃
(C) Ethyl ethanoate, CH₃COOC₂H₅

Question 2.
Write the IUPAC names of the following compounds.
Answer:

Students can download 10th Science Chapter 9 Solutions Questions and Answers, Notes, Samacheer Kalvi 10th Science Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

Tamilnadu Samacheer Kalvi 10th Science Solutions Chapter 9 Solutions

Samacheer Kalvi 10th Science Solutions Text Book Back Questions and Answers

I. Choose the best answer:

Question 1.
A solution is a mixture.
(a) homogeneous
(b) heterogeneous
(c) homogeneous and heterogeneous
(d) non-homogeneous
Answer:
(a) homogeneous

Question 2.
The number of components in a binary solution is ______.
(a) 2
(b) 3
(c) 4
(d) 5.
Answer:
(a) 2

Question 3.
Which of the following is the universal solvent?
(a) Acetone
(b) Benzene
(c) Water
(d) Alcohol
Answer:
(c) Water

Question 4.
A solution in which no more solute can be dissolved in a definite amount of solvent at a given temperature is called ______.
(a) Saturated solution
(b) Un saturated solution
(c) Supersaturated solution
(d) Dilute solution.
Answer:
(a) Saturated solution

Question 5.
Identify the non-aqueous solution.
(a) sodium chloride in water
(b) glucose in water
(c) copper sulphate in water
(d) sulphur in carbon-di-sulphide
Answer:
(d) sulphur in carbon-di-sulphide

Question 6.
When pressure is increased at a constant temperature the solubility of gases in liquid ______.
(a) No change
(b) increases
(c) decreases
(d) no reaction.
Answer:
(b) increases

Question 7.
Solubility of NaCl in 100 ml water is 36 g. If 25 g of salt is dissolved in 100 ml of water how much more salt is required for saturation:
(a) 12 g
(b) 11 g
(c) 16 g
(d) 20 g
Answer:
(b) 11 g

Question 8.
A 25% alcohol solution means ______.
(a) 25 ml of alcohol in. 100 ml of water
(b) 25 ml of alcohol in 25 ml of water
(c) 25 ml of alcohol in 75 ml of water
(d) 75 ml of alcohol in 25 ml of water.
Answer:
(c) 25 ml of alcohol in 75 ml of water

Question 9.
Deliquescence is due to:
(a) Strong affinity to water
(b) Less affinity to water
(c) Strong hatred to water
(d) Inertness to water
Answer:
(a) Strong affinity to water

Question 10.
Which of the following is hygroscopic in nature?
(a) ferric chloride
(b) copper sulphate pentahydrate
(c) silica gel
(d) none of the above.
Answer:
(c) silica gel

II. Fill in the blanks:

1. The component present in lesser amount, in a solution is called ……..
2. Example for liquid in solid type solution is ……….
3. Solubility is the amount of solute dissolved in ……… g of solvent.
4. Polar compounds are soluble in ……… solvents.
5. Volume percentage decreases with increases in temperature because ………

Answer:

1. solute
2. amalgam
3. 100
4. Polar
5. of expansion of liquid

III. Match the following:

Answer:
A. (iii)
B. (i)
C. (iv)
D. (ii)

IV. True or False: (If false give the correct statement):

1. Solutions which contain three components are called binary solution.
2. In a solution the component which is present in lesser amount is called solvent.
3. Sodium chloride dissolved in water forms a non-aqueous solution.
4. The molecular formula of green vitriol is MgSO₄. 7H₂O
5. When Silica gel is kept open, it absorbs moisture from the air, because it is hygroscopic in nature.

Answer:

1. False – Solutions which contain two components are called binary solution.
2. False – In a solution the component which is present in lesser amount is called solute.
3. False – Sodium chloride dissolved in water forms an aqueous solution.
4. False – The molecular formula of green vitriol is FeSO₄. 7H₂O
5. True

V. Short Answer Questions:

Question 1.
Define the term: Solution
Answer:
A solution is a homogeneous mixture of two or more substances.

Question 2.
What is mean by the binary solution?
Answer:
A solution must at least be consisting of two components. Such solutions which are made of one solute and one solvent are called binary solutions.
E.g., On adding CuSO₄ crystals to water.

Question 3.
Give an example each

1. gas in liquid;
2. solid in liquid;
3. solid in solid;
4. gas in gas.

Answer:

1. Gas in liquid – CO₂ in water
2. Solid in liquid – NaCl in water
3. Solid in solid – Alloys
4. Gas in gas – He – O₂ gas

Question 4.
What is the aqueous and non-aqueous solution? Give an example.
Answer:
Aqueous solution: The solution in which water act as a solvent is called aqueous solution. In general, ionic compounds are soluble in water and form aqueous solutions more readily than covalent compounds. E.g. Common salt in water.

Non – Aqueous solution: The solution in which any liquid, other than water act as a solvent is called non-aqueous solution. Alcohols, benzene, ethers, etc., are used as non – aqueous solvents. E.g. Sulphur dissolved in carbon disulphide.

Question 5.
Define Volume percentage.
Answer:
Volume percentage is defined as the percentage by volume of solute (in ml) present in the given volume of solution.

Question 6.
The aquatic animals live more in a cold region. Why?
Answer:
Aquatic animals live more in cold regions because the solubility of oxygen is more in cold water (at low temperature). Therefore, aquatic animals are more comfortable in cold water.

Question 7.
Define Hydrated salt.
Answer:
Ionic substances which crystallise out from their saturated aqueous solution with a definite number of molecules of water are called hydrated salts.

Question 8.
A hot saturated solution of copper sulphate forms crystals as it cools. Why?
Answer:
The capability of a solution to maintain a certain concentration of solute is temperature-dependent. When a saturated solution of copper sulphate at above room temperature is allowed to cool, the solution becomes supersaturated and in the absence of stirring or the return of the previous solution temperature, the solute starts to precipitate out. i.e., crystal formation occurs.

Question 9.
Classify the following substances into deliquescent, hygroscopic. Cone. Sulphuric acid, Copper sulphate penta hydrate, Silica gel, Calcium chloride and Gypsum salt.
Answer:

VI. Long answer questions:

Question 1.
Write notes on?

1. saturated solution
2. unsaturated solution

Answer:

1. Saturated solution: A solution in which no more solute can be dissolved in a definite amount of the solvent at a given temperature is called saturated solution, e.g. 36 g of sodium chloride in 100 g of water at 25°C forms a saturated solution.
2. Unsaturated solution: Unsaturated solution is one that contains less solute than that of the saturated solution at a given temperature, e.g. 10 g or 20 g or 30 g of Sodium chloride in 100 g of water at 25°C forms an unsaturated solution.

Question 2.
Write notes on various factors affecting solubility.
Answer:
There are three main factors which affects the solubility of a solute. They are

1. Nature of the solute and solvent
2. Temperature
3. Pressure

1. Nature of the solute and solvent : The nature of the solute and solvent plays an important role in solubility. Even though water is Universal solvent, all substances do not dissolve in water. Dissolution occurs when similarities exist between the solvent and the solute.

Ionic compounds are soluble in polar solvent like water and covalent compounds are soluble in non-polar solvents like ether, benzene, alcohol etc.

2. Effect of Temperature :
Solubility of solid in liquid : Generally solubility of a solid solute in a liquid increases with increase in temperature.
In Endothermic process : Solubility increases with increase in temperature.
In Exothermic process : Solubility decreases with increase in temperature.
Solubility of Gases in liquid : Solubility of gases in liquid decreases with increase in temperature.

3. Effect of Pressure : Effect of pressure is observed only in the case of solubility of a gas in a liquid. When the pressure is increased, the solubility of a gas in liquid increases.

Question 3.
(a) What happens when MgSO₄.7H₂O is heated? Write the appropriate equation
(b) Define solubility.
Answer:
(a) When Epsom salt MgSO₄.7H₂O crystals are gently heated, it loses seven water molecules and becomes anhydrous MgSO₄.

(b) Solubility is defined as the amount of solute in grams that can be dissolved in 100 g of the solvent to form its saturated solution at a given temperature and pressure.

Question 4.
In what way hygroscopic substances differ from deliquescent substances.
Answer:

Question 5.
A solution is prepared by dissolving 45 g of sugar in 180 g of water. Calculate the mass percentage of solute.
Answer:
Mass of the solute (sugar) = 45 g
Mass of the solvent (Water) = 180 g
Formula:
Mass percentage of solute (sugar)

The mass percentage of solute = 20%

Question 6.
3.5 litres of ethanol is present in 15 litres of aqueous solution of ethanol. Calculate volume percent of ethanol solution.
Answer:
Volume of ethanol = 3.5 lit = 3500 ml
Volume of water = 15 lit = 15000 ml
Formula:

The volume percentage of ethanol solution = 18.92

VII. HOT Questions

Question 1.
Vinu dissolves 50 g of sugar in 250 ml of hot water, Sarath dissolves 50 g of same sugar in 250 ml of cold water. Who will get a faster dissolution of sugar? and Why?
Answer:
Vinu will get a faster dissolution of sugar. Because generally solubility of a solid solute in a liquid solvent increases with increase in temperature. Therefore Vinu dissolves 50 g of sugar in 250 ml of hot water than Sarath dissolves 50 g of sugar in 250 ml of cold water.

Question 2.
‘A’ is a blue coloured crystalline salt. On heating it loses blue colour and to give ‘B’ When water is added, ‘B’ gives back to ‘A’. Identify A and B, write the equation.
Answer:
Since ‘A’ is a blue coloured crystalline salt, it is CuSO₄. 5H₂O (Blue vitriol). On heating it loses all five water molecules and becomes colourless anhydrous CuSO₄.

When water is added ‘B’ gives back A.

Question 3.
Will the cool drinks give more fizz at top of the hills or at the foot? Explain.
Answer:
At hilltops, the temperature will become less and pressure also decreases. Because temperature and pressure are directly proportional to each other. At low-pressure carbonate, cool drinks will give less fizz and give more fizz at the foot.

Samacheer Kalvi 10th Science Solutions Additional Important Questions and Answers

I. Choose the correct answer:

Question 1.
The dissolution of sugar and salt in water results in a solution.
(a) Binary
(b) Ternary
(c) Quaternary
(d) Saturated
Answer:
(b) Ternary

Question 2.
In a solution, the component which is present in a lesser amount is called ______.
(a) solvent
(b) dissolution
(c) solute
(d) mole.
Answer:
(c) solute

Question 3.
The supersaturated solution of NaCl in 100 g of water at 25°C contains:
(a) 40 g of NaCl
(b) 10 g of NaCl
(c) 20 g of NaCl
(d) 30 g of NaCl
Answer:
(a) 40 g of NaCl

Question 4.
How many component(s) present in binary solution?
(a) 1
(b) 2
(c) 3
(d) 4.
Answer:
(b) 2

Question 5.
Formalin is an aqueous solution of:
(a) formic acid
(b) ammonia
(c) formaldehyde
(d) carbon tetrachloride
Answer:
(c) formaldehyde

Question 6.
The effect of pressure on the solubility of a gas in liquids is given by:
(a) Boyle’s Law
(b) Charle’s Law
(c) Henry’s Law
(d) Avogadro’s Law
Answer:
(c) Henry’s Law

Question 7.
Which one of the following is an example of an aqueous solution?
(a) Sugar in water
(b) Sulphur in carbon disulphide
(c) Iodine dissolved in carbon tetrachloride
(d) Benzoic acid in ethers.
Answer:
(a) Sugar in water

Question 8.
The type of solution when CO₂ is dissolved in water:
(a) solid/liquid
(b) liquid in liquid
(c) gas in liquid
(d) liquid in solid
Answer:
(c) gas in liquid

Question 9.
Tin amalgam is an example of ……… solution.
(a) solid in solid
(b) liquid in solid
(c) solid in liquid
(d) liquid in liquid
Answer:
(b) liquid in solid

Question 10.
In which case solubility decreases with increase in temperature?
(a) Endothermic process
(b) Exothermic process
(c) Both (a) and (b)
(d) None of these.
Answer:
(b) Exothermic process

Question 11.
Fat is soluble in:
(a) water
(b) alcohol
(c) CCl₄
(d) ether
Answer:
(d) ether

Question 12.
The deliquescent substance among the following is:
(a) con.H₂SO₄
(b) P₂O₅
(c) CaCl₂
(d) SiO₂
Answer:
(c) CaCl₂

Question 13.
Mass percentage is expressed as ______.
(a) v/v
(b) w/w
(c) v/w
(d) w/v.
Answer:
(b) w/w

Question 14.
Hygroscopic substances are used as ……… agents.
(a) foaming
(b) drying
(c) oxidising
(d) reducing
Answer:
(b) drying

Question 15.
The molecular formula of Epsom salt is ______.
(a) CuSO₄.5H₂O
(b) FeSO₄.7H₂O
(c) MgSO₄.7H₂O
(d) ZnSO₄.7H₂O.
Answer:
(c) MgSO₄.7H₂O

II. Fill in the blanks:

1. A true solution is a ……… mixture of solute and solvent.
2. Soil cannot store more nitrogen than it can hold because soil is said to be in a state of ………
3. In the dissolution of NaOH in water, the solubility …….. with increase in temperature.
4. Aquatic animals are more comfortable in cold water because as the temperature is less the solubility of dissolved oxygen ………
5. Hydrated salts contain ……… of crystallization.
6. He-O₂ mixture is a binary solution of …….. in ………. solution.
7. The solvent used for dissolving Sulphur is ……….
8. The solubility of NaOH at 25°C is ……….
9. According to Henry’s Law, the solubility of a gas in liquid is ………. proportional to the pressure of the gas over the solution at definite temperature.
10. Anhydrous Calcium chloride is a ………. substance.
11. ……… substances absorb enough water from the atmosphere and get completely dissolved.
12. When 90g of sodium bromide is dissolved in 100 g of water at 25°C it forms a ………. solution.
13. ………. is an example of a binary solution with liquid in Gas.
14. Air and sea water are important ……… solution.
15. A quaternary solution contains ……….. components.
16. The primary factor which determines the characteristic of a solution is ………..
Answer:
1. Homogeneous
2. saturation
3. decreases
4. increases
5. water
6. Gas, Gas
7. CS₂ (or) Carbon disulphide
8. 80 g
9. directly
10. Hygroscopic
11. deliquescent
12. Unsaturated
13. Cloud
14. Homogeneous
15. four
16. Physical state

III. Match the following

Question 1.
Match the column I with column II.

Answer:
A. (iv)
B. (iii)
C. (v)
D. (ii)
E. (i)

Question 2.
Match the column I with column II.

Answer:
A. (iii)
B. (iv)
C. (v)
D. (ii)
E. (i)

Question 3.
Match the column I with column II.

Answer:
A. (v)
B. (iii)
C. (ii)
D. (i)
E. (iv)

Question 4.
Match the column I with column II.

Answer:
A. (iii)
B. (iv)
C. (v)
D. (i)
E. (ii)

Question 5.
Match the column I with column II.

Answer:
A. (iv)
B. (iii)
C. (i)
D. (v)
E. (ii)

IV. True or False: (If false give the correct statement)

1. In an aqueous solution of copper sulphate, the solvent is copper sulphate.
2. A solution containing sugar and salt in water is a binary solution.
3. An example of a solid solution is alloy.
4. The difference between concentrated and dilute solution can be observed by means of colour (or) density.
5. A saturated solution contains 91 g of Glucose in 100 g of water at 25°C.
6. Fat is dissolved in the aqueous solvent ether.
7. The solubility of a gas in a liquid is inversely proportional to the pressure of the gas at a definite temperature.
8. Mass percentage of a solution is expressed as .
9. The white vitriol is represented by the formula ZnSO₄ . 7H₂O.
10. Ferric chloride is a Hygroscopic substance.
Answer:
1. False – In an aqueous solution of copper sulphate, the solvent is water.
2. False – A solution containing sugar and salt in water is a ternary solution.
3. True
4. True
5. True
6. False – Fat is dissolved in the non-aqueous solvent ether.
7. False – The solubility of a gas in a liquid is directly proportional to the pressure of the gas at a definite temperature.
8. True
9. True
10. False – Ferric chloride is a deliquescent substance.

V. Short answer questions:

Question 1.
(i) Which gas is dissolved in soft drinks?
(ii) What will you do to increase the solubility of this gas?
Answer:
(i) Carbon-di-oxide (CO₂) is dissolved in soft drinks.
(ii) An increase in pressure will increase the solubility of CO₂ gas.

Question 2.
Identify the type of binary solution given below.
Answer:

1. Alloys
2. Amalgam
3. Ethyl alcohol in water
4. Aerated drinks

Answer:

1. Solid in solid
2. liquid in solid
3. liquid in liquid
4. Gas in liquid

Question 3.
Explain why Nitrogen in soil is called a saturated solution in nature?
Answer:
Nitrogen in soil is an example of a saturated solution in nature. Soil cannot store more Nitrogen than it can hold.

Question 4.
Define Mass percentage.
Answer:
Mass percentage of a solution is defined as the percentage by mass of the solute present in the solution.

Question 5.
Define the term Molarity (M).
Answer:

Question 6.
Define the term Molality (m).
Answer:

Question 7.
Define the supersaturated solution.
Answer:
A supersaturated solution is one that contains more solute than the saturated solution at a given temperature.
E.g. 40 g of sodium chloride in 100 g of water at 25°C.

Question 8.
Justify the following statements with an explanation.
(i) Solubility of NH₄Cl increases with increase in temperature.
Answer:
Solubility of NH₄Cl increases with increase in temperature because it is an endothermic process.

(ii) Solubility of NaOH decreases with increase in temperature.
Answer:
Solubility of NaOH decreases with increase in temperature because it is an exothermic process.

Question 9.
Calculate the molarity of a solution containing 4 g of NaOH in 500 ml of water.
Answer:
Mass of NaOH = 4 g
Volume of solution = 500 ml

= 0.1 × 2
= 0.2 M

Question 10.
Calculate the molality of a solution containing 3 g of urea (molecular mass = 60) in 750 g of water.
Answer:
Mass of urea (solute) = 3 g
Mass of water (solvent) = 750 g
Formula:

Question 11.
Define dissolution.
Answer:
The process of uniform distribution of solute into solvent is called dissolution.

VI. Long answer questions:

Question 1.
Answer the blanks given in the table.
Answer:

Question 2.
Write a note on the type of solution based on the type of solvent.
Answer:
(i) Aqueous solution : The solution in which water acts as a solvent is called aqueous solution. In general, ionic compounds are soluble in water and form aqueous solutions more readily than covalent compounds.
Eg: Common salt in water, Sugar in water, Copper sulphate in water etc..

(ii) Non-Aqueous solution : The solution in which any liquid, otter than water, acts as a solvent is called non-aqueous solution. Solvent other than water is referred to as non-aqueous solvent. Generally, alcohols, benzene, ethers, carbon disulphide, acetone, etc., are used as non- aqueous solvents.
Eg: Sulphur dissolved in carbon disulphide, Iodine dissolved in carbon tetrachloride.

Question 3.
Justify the following statements with an explanation.

1. The solubility of calcium oxide decreases with increase in temperature,
2. What happens to the solubility in the exothermic process with regard to temperature?
3. In the endothermic process, solubility increases with increase in temperature.
4. At a given temperature, an increase in pressure increases the solubility of the gas

Answer:

1. In an exothermic process, the solubility decreases. When calcium oxide dissolves in water, an exothermic reaction takes place, and so the solubility of calcium oxide decreases
2. In an exothermic process, the solubility decreases with the increase in temperature, as there is already an evolution of heat and it is observed.
3. In an endothermic process, the solubility increases. The solubility of KNO₃ in water is an endothermic reaction and so solubility increases with the increase of temperature.
4. At a given temperature, an increase in pressure increases the solubility of gas according to Henry’s law. e.g. (CO₂ in soft drinks)

VII. Hot Questions.

Question 1.
50 ml tincture of benzoin, antiseptic solution contains 10 ml of benzoin. Calculate the volume of percentage of benzoin.
Answer:
Volume of the solute, Benzoin = 10 ml
Volume of the solution, tincture of benzoin = 50 ml

= 20% (v/v)

Question 2.
Neomycin, the antibiotic cream contains 300 mg of neomycin sulphate the active ingredient in 30 g of ointment base. Calculate the mass percentage of neomycin.
Answer:
Mass of neomycin sulphate(solute) = 300 mg
Mass of the ointment (solution) = 30 g
Formula:

VIII. Numerical problems:

Question 1.
Calculate the molality of the solution containing 18 g of Glucose (Molecular mass 180) in 2 kg of water.
Answer:
Mass of Glucose = 18 g
Molecular mass of Glucose = 180

= 0. 05 m

Question 2.
Calculate the molarity of a solution containing 5.85 g of sodium chloride in 500 ml of the water. (Molecular mass = 58.5)
Answer:
Mass of the solute = 5.85 g
Volume of the solution = 500
No. of moles of NaCl = \(\frac{5.85}{58.5}\) = 0.1

= \(\frac{0.1}{500}\) × 1000 = 0.2 M

Students can download 10th Science Chapter 8 Periodic Classification of Elements Questions and Answers, Notes, Samacheer Kalvi 10th Science Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

Tamilnadu Samacheer Kalvi 10th Science Solutions Chapter 8 Periodic Classification of Elements

Samacheer Kalvi 10th Science Periodic Classification of Elements Text Book Back Questions and Answers

I. Choose the best answer:

Question 1.
The number of periods and groups in the periodic table are:
(a) 6, 16
(b) 7, 17
(c) 8, 18
(d) 7, 18
Answer:
(d) 7, 18

Question 2.
The basis of modem periodic law is ____.
(a) atomic number
(b) atomic mass
(c) isotopic mass
(d) number of neutrons.
Answer:
(a) atomic number

Question 3.
……….. group contains the member of the halogen family.
(a) 17th
(b) 15th
(c) 18th
(d) 16th
Answer:
(a) 17th

Question 4.
_______ is a relative periodic property.
(a) atomic radii
(b) ionic radii
(c) electron affinity
(d) electronegativity.
Answer:
(b) ionic radii

Question 5.
Chemical formula of rust is:
(a) Fe0.xH₂O
(b) Fe04.xH₂O
(c) Fe₂O₃. xH₂O
(d) FeO
Answer:
(c) Fe₂O₃. xH₂O

Question 6.
In the aluminothermic process the role of Al is:
(a) oxidizing agent
(b) reducing agent
(c) hydrogenating agent
(d) sulphurising agent
Answer:
(b) reducing agent

Question 7.
The process of coating the surface of the metal with a thin layer of zinc is called ____.
(a) painting
(b) thinning
(c) galvanization
(d) electroplating.
Answer:
(c) galvanization

Question 8.
Which of the following inert gas has electrons in the outermost shell?
(a) He
(b) Ne
(c) Ar
(d) Kr
Answer:
(a) He

Question 9.
Neon shows zero electron affinity due to ____.
(a) stable arrangement of neutrons
(b) stable configuration of electrons
(c) reduced size
(d) increased density.
Answer:
(b) stable configuration of electrons

Question 10.
……….. is an important metal to form amalgam.
(a) Ag
(b) Hg
(c) Mg
(d) Al
Answer:
(b) Hg

II. Fill in the blanks:

1. If the electronegativity difference between two bonded atoms in a molecule is greater than 1.7, the nature of bonding is ………..
2. …………. is the longest period in the periodical table.
3. ………… forms the basis of modern periodic table.
4. If the distance between two Cl atoms in Cl₂ molecule is 1.98 Å, then the radius of Cl atom is ………..
5. Among the given species A^– A⁺, and A, the smallest one in size is ……….
6. The scientist who propounded the modern periodic law is …………
7. Across the period, ionic radii ………… (increases,decreases).
8. ……….. and ………… are called inner transition elements.
9. The chief ore of Aluminium is ………….
10. The chemical name of rust is ………….
Answer:
1. ionic
2. 6th (sixth) period
3. Atomic number
4. 0.99 Å
5. A⁺
6. Dimitri Mendeleev
7. decreases
8. Lanthanides, Actinides
9. bauxite
10. hydrated ferric oxide

III. Match the following:

Answer:
A. (ii)
B. (v)
C. (iv)
D. (iii)
E. (i)

IV. True or False: (If false give the correct statement)

1. Moseley’s periodic table is based on atomic mass.
2. Ionic radius increases across the period from left to right.
3. All ores are minerals; but all minerals cannot be called as ores.
4. Aluminium wires are used as electric cables due to their silvery white colour.
5. An alloy is a heterogenous mixture of metals.
Answer:
1. False – Moseley’s periodic table is based on atomic number.
2. True
3. True
4. False – Aluminium wires are used as electric cables because it is a good conductor of heat and electricity.
5. False – An alloy is an homogeneous mixture of metals.

V. Assertion and Reason:

Answer the following questions using the data given below:
Question 1.
Assertion: The nature of bond in HF molecule is ionic.
Reason: The electronegativity difference between H and F is 1.9.
(a) Assertion and Reason are correct, Reason explains the Assertion.
(b) Assertion is correct, Reason is wrong.
(c) Assertion is wrong, Reason is correct.
(d) Assertion and Reason are correct, Reason doesn’t explains Assertion.
Answer:
(a) Assertion and Reason are correct, Reason explains the Assertion.

Question 2.
Assertion: Magnesium is used to protect steel from rusting.
Reason: Magnesium is more reactive than iron.
(a) Assertion and Reason are correct, Reason explains the Assertion.
(b) Assertion is correct, Reason is wrong.
(c) Assertion is wrong, Reason is correct.
(d) Assertion and Reason are correct, Reason doesn’t explains Assertion.
Answer:
(a) Assertion and Reason are correct, Reason explains the Assertion.

Question 3.
Assertion: An uncleaned copper vessel is covered with greenish layer. Reason: copper is not attacked by alkali.
(a) Assertion and Reason are correct, Reason explains the Assertion.
(b) Assertion is correct, Reason is wrong.
(c) Assertion is wrong, Reason is correct.
(d) Assertion and Reason are correct, Reason doesn’t explains Assertion.
Answer:
(d) Assertion and Reason are correct, Reason doesn’t explains Assertion.

VI. Short answer questions:

Question 1.
A is a reddish brown metal, which combines with O₂ at < 1370 K gives B, a black coloured compound. At a temperature > 1370 K, A gives C which is red in colour. Find A, B and C with reaction.
Answer:
(A) is a reddish brown metal – Copper

A – Copper; B – Cupric oxide; C – Cuprous oxide.

Question 2.
A is a silvery white metal. A combines with O₂ to form B at 800°C, the alloy of A is used in making the aircraft. Find A and B.
Answer:
A – Silvery white metal – Aluminium

The alloys of aluminium, Duralumin and Magnalium are used in making the aircraft.
A – Aluminium; B – Aluminium oxide.

Question 3.
What is rust? Give the equation for the formation of rust.
Answer:
When iron is exposed to moist air, it forms a layer of brown hydrated ferric oxide on its surface. This compound is known as rust and the phenomenon of formation of rust is known as rusting.
4Fe + 3O₂ + xH₂O → 2Fe₂O₃. xH₂O (Rust).

Question 4.
State two conditions necessary for rusting of iron.
Answer:
(i) The presence of water and oxygen is essential for the rusting of iron.
(ii) Impurities in the iron, the presence of water vapour, acids, salts and CO₂ speeds up rusting.

VII. Long answer questions:

Question 1.
(a) State the reason for addition of caustic alkali to bauxite ore during purification of bauxite.
Answer:
Caustic alkali is added to bauxite, to dissolve bauxite ore and obtain a solution of sodium aluminate.

(b) Along with cryolite and alumina, another substance is added to the electrolyte mixture. Name the substance and give one reason for the addition.
Answer:
CaF₂ (Fluorspar) is added along with cryolite and alumina. It is added to reduce the high melting point of the electrolyte.

Question 2.
The electronic configuration of metal A is 2, 8, 18, 1.
The metal A when exposed to air and moisture forms B a green layered compound. A with con. H₂SO₄ forms C and D along with water. D is a gaseous compound. Find A, B, C and D.
Answer:
Metal (A) with electronic configuration- 2, 8, 18, 1 is copper.
2Cu + O₂ + CO₂ + H₂O → CuCO₃. Cu(OH)₂ (B)
Copper carbonate (Green layer)

(A) – Copper (Cu)
(B) – Copper Carbonate (CuCO₃. Cu(OH)₂)
(C) – Copper Sulphate (CuSO₄)
(D) – Sulphur dioxide (SO₂)

Question 3.
Explain the smelting process.
Answer:
The roasted ore of copper is mixed with powdered coke and sand and is heated in a blast furnace to obtain matte (Cu₂S + FeS) and slag. The slag is removed as waste.
2 FeS + 3O₂ → 2 FeO + 2 SO₂
2 Cu₂S + 3O₂ → 2 Cu₂O + 2SO₂
Cu₂O + FeS → Cu₂S + FeO
FeO + SiO₂ → FeSiO₂ (slag)

VIII. HOT questions:

Question 1.
Metal A belongs to period 3 and group 13. A in red hot condition reacts with steam to form B. A with strong alkali forms C. Find A, B and C with reactions.
Answer:
Metal A belongs to Period 3 and Group 13. So metal ‘A’ is aluminium.
(A) in red hot condition reacts with steam to form ‘B’.

‘A’ with strong alkali forms ‘C’

(A) – Aluminium
(B) – Aluminium oxide
(C) – Sodium meta aluminate

Question 2.
Name the acid that renders aluminium passive. Why?
Answer:
Dilute or concentrated nitric acid (HNO₃) renders aluminium passive. Because nitric acid does not attack aluminium but it renders aluminium passive due to the formation of an oxide film on its surface.

Question 3.
(a) Identify the bond between H and F in HF molecule.
Answer:
Ionic, because the electronegativity difference is more than 1.7.

(b) What property forms the basis of identification?
Answer:
Electronegativity.

(c) How does the property vary in periods and in groups?
Answer:
In a period, from left to right the electronegativity increases because of the increase in the nuclear charge.
In a Group, from top to bottom, the electronegativity decreases because of the increase in size of the elements.

Samacheer Kalvi 10th Science Periodic Classification of Elements Additional Important Questions and Answers

I. Choose the correct answer:

Question 1.
The shortest period in the periodic table contains elements.
(a) 18
(b) 8
(c) 2
(d) 32
Answer:
(c) 2

Question 2.
Group number of carbon family is _____.
(a) 13
(b) 15
(c) 17
(d) 14.
Answer:
(d) 14.

Question 3.
The ore forming elements, chalcogens are present in ……… group of the modern periodic table.
(a) 18th
(b) 1st
(c) 2nd
(d) 16th
Answer:
(d) 16th

Question 4.
Valency of all the alkali metals is _____.
(a) 1
(b) 2
(c) 3
(d) 4.
Answer:
(a) 1

Question 5.
The largest atom in the 2nd period of the periodic table is:
(a) Li
(b) Be
(c) F
(d) Ne
Answer:
(a) Li

Question 6.
The covalent radii of Hydrogen, if the distance between the Hydrogen nuclei of the molecule is 0.74 Å is:
(a) 1.58 Å
(b) \(\frac{0.74}{4}\) Å
(c) 0.37 Å
(d) 0.74 Å
Answer:
(c) 0.37 Å

Question 7.
Pick out the correct ionic radii in increasing order for the following species – Na, Cl, Na⁺, Cl^– _____.
(a) Na > Cl > Na⁺ > Cl^–
(b) Cl > Na > Na⁺ > Cl^–
(c) Cl^– > Na > Na⁺ > Cl
(d) Cl < Na⁺ < Cl^– < Na.
Answer:
(d) Cl < Na⁺ < Cl^– < Na.
Hint:
Na = 186 pm,
Cl = 91 pm,
Na⁺ = 116 pm,
Cl^– = 167 pm.

Question 8.
In the third period, the first ionization potential is of the order:
(a) Na > Al > Mg > Si > P
(b) Mg > Na > Si > P > Al
(c) Na < Al < Mg < Si < P
(d) Na < Al < Mg < Si < P
Answer:
(c) Na < Al < Mg < Si < P

Question 9.
Which one of the following is the least electronegative element?
(a) Bromine
(b) Chlorine
(c) Iodine
(d) Hydrogen
Answer:
(d) Hydrogen

Question 10.
Which is a widely used a scale to determine the electronegativity?
(a) Pauling scale
(b) Moseley scale
(c) Mendeleev scale
(d) none of these.
Answer:
(a) Pauling scale

Question 11.
Which one of the following orders of ionic radii is correct?
(a) H^– > H⁺ > H
(b) Na⁺ > F^– > O^2-
(c) F > O^2- > Na⁺
(d) None of these
Answer:
(d) None of these

Question 12.
The percentage of carbon in Pig iron is:
(a) < 0.25%
(b) 0.25 – 2%
(c) 2 – 4.5%
(d) > 5%
Answer:
(c) 2 – 4.5%

Question 13.
The chemical formula of clay is _____.
(a) Al₂O₃
(b) Al₂O₃.2H₂O
(c) Al₂O₃. 2SiO₂.2H₂O
(d) Al₂O₃. 2SiO₂.H₂O.
Answer:
(c) Al₂O₃. 2SiO₂.2H₂O

Question 14.
The temperature in the combustion zone is maintained at:
(a) 1500°C
(b) 400°C
(c) 1000°C
(d) 1380°C
Answer:
(a) 1500°C

Question 15.
Oil used in Froth floatation method is _____.
(a) pine oil
(b) natural oil
(c) crude oil
(d) Synthetic oil.
Answer:
(a) pine oil

Question 16.
The first most abundant metal present in the Earth crust is:
(a) Iron
(b) Aluminium
(c) Zinc
(d) Copper
Answer:
(b) Aluminium

Question 17.
……….. metal is used for making calorimeters.
(a) Copper
(b) Tin
(c) Mercury
(d) Iron
Answer:
(a) Copper

Question 18.
More reactive metal is _____.
(a) Zn
(b) Fe
(c) Ag
(d) Na.
Answer:
(d) Na.

Question 19.
The chief ore of Iron is:
(a) Magnesite
(b) Galena
(c) Cinnabar
(d) Haematite
Answer:
(d) Haematite

Question 20.
The metal which melts at room temperature is:
(a) Zinc
(b) Lead
(c) Gallium
(d) Tin
Answer:
(c) Gallium

Question 21.
Conversion of bauxite into alumina is _____.
(a) Hall’s process
(b) Alumino thermic process
(c) Baeyer’s process
(d) Bessemerisation process.
Answer:
(c) Baeyer’s process

Question 22.
………. metal can be cut with knife.
(a) Potassium
(b) Gallium
(c) Mercury
(d) Gold
Answer:
(a) Potassium

Question 23.
………. is not a good conductor of heat and electricity.
(a) Silver
(b) Tungsten
(c) Copper
(d) Aluminium
Answer:
(b) Tungsten

Question 24.
Electrolyte used in Hall’s process ______.
(a) Pure alumina + molten cryolite + fluorspar
(b) Pure alumina + molten bauxite + fluorspar
(c) Pure bauxite + molten cryolite + fluorspar
(d) Pure bauxite + molten Haematite + fluorspar.
Answer:
(a) Pure alumina + molten cryolite + fluorspar

Question 25.
The foaming agent used for froth floatation process is:
(a) Coconut oil
(b) Pine oil
(c) Sodium chloride
(d) Groundnut oil
Answer:
(b) Pine oil

Question 26.
Three elements A, B and C are having the electronic configuration Is² 2s¹, Is² 2s² and Is² 2s² 2p¹ respectively. Which element will have the lowest ionization energy?
(a) A
(b) B
(c) C
(d) B and C
Answer:
(a) A

Question 27.
Metal used in household utensils is ______.
(a) Al
(b) Co
(c) Fe
(d) Na.
Answer:
(a) Al

Question 28.
Which one of the following pair is a metalloid?
(a) Na and K
(b) F and Cl
(c) Cu and Hg
(d) Si and Ge
Answer:
(d) Si and Ge

Question 29.
The highly metallic element will have the configuration of:
(a) 2, 8, 7
(b) 2, 8, 8, 5
(c) 2, 8, 8, 1
(d) 2, 8, 2
Answer:
(c) 2, 8, 8, 1

Question 30.
The metal used in electroplating is ______.
(a) Cu
(b) Al
(c) Fe
(d) Co.
Answer:
(a) Cu

Question 31.
The flux which is used when the gangue present in the ore is acidic:
(a) Silica
(b) Calcium oxide
(c) Calcium silicate
(d) Cuprous sulphide
Answer:
(b) Calcium oxide

Question 32.
Matte is a mixture of:
(a) Cu₂O + Cu₂S
(b) Cu₂O + FeS
(c) Cu₂S + FeS
(d) Cu₂O + PbS
Answer:
(c) Cu₂S + FeS

Question 33.
Fe reacts with dilute nitric acid in cold condition to give ______.
(a) Ferrous nitride
(b) Ferrous nitrate
(c) Ferric nitride
(d) Ferric nitrate.
Answer:
(b) Ferrous nitrate

Question 34.
In the brass alloy, which is solvent?
(a) Zn
(b) Co
(c) Ag
(d) Cu.
Answer:
(d) Cu.

II. Fill in the blanks:

1. The major component of the matte is ………….
2. The modern periodic table is based on ………..
3. The valency of alkali metals is …………
4. The unreactive elements are present in group ………..
5. In the 2nd period, the smallest atom is ……….
6. The size of a cation is ………… than the neutral atom.
7. ……….. is the unit of ionization energy.
8. The ionization energy ……… down the group in the periodic table.
9. The electron affinities of noble gases are …………
10. ………. is the process of extracting the ore from the Earth’s crust.
11. Galena is the ore of …………..
12. The silvery white metal which is a good conductor of heat and electricity is …………
13. The slag formed during Bessemerisation process is ………….
14. Blister copper contains ………. percentage of copper.
15. Haematite ore is concentrated by ……….. washing.
Answer:
1. Cu₂S
2. atomic number
3. one
4. 18
5. Neon
6. smaller
7. KJ/mol
8. decreases
9. zero
10. Mining
11. lead
12. aluminium
13. Iron silicate or FeSiO₃
14. 98%
15. hydraulic

III. Match the following:

Question 1.
Match the column I with column II.

Answer:
A. (iv)
B. (v)
C. (i)
D. (ii)
E. (iii)

Question 2.
Match the column I with column II.

Answer:
A. (ii)
B. (iv)
C. (v)
D. (iii)
E. (i)

Question 3.
Match the column I with column II.

Answer:
A. (iii)
B. (iv)
C. (v)
D. (i)
E. (ii)

Question 4.
Match the column I with column II.

Answer:
A. (v)
B. (iv)
C. (ii)
D. (iii)
E. (i)

IV. True or false. (If false give the correct statement)

1. Alkali metals are generally extracted by the electrolysis of their ores in fused state.
2. Every mineral is an ore but every ore is not a mineral.
3. Slag is a product formed during smelting by combination of flux and impurities.
4. Reactive metals occur in native state.
5. Malachite is a sulphide ore of copper.
6. Lanthanides are present in the 6th group of the periodic table.
7. Atomic radius increases as we go across the period due to increase in size.
8. As the positive charge increases, the size of the cation decreases.
9. If the difference in electronegativity is greater than 1.7, the bond is considered to be covalent.
10. Siderite is the carbonate ore of calcium.
Answer:
1.True
2. True
3. True
4. False – Reactive metals always occur in the combined state.
5. False – Malachite is the carbonate ore of copper.
6. False – Lanthanides are present in the 6th period of the periodic table.
7. False – Atomic radius increases as we go across the period due to decrease in size.
8. True
9. False – If the difference in electronegativity is greater than 1.7, the bond is considered to be ionic.
10. False – Siderite is the carbonate ore of Iron.

V. Assertion and Reason:

Answer the following questions using the data given below:
Question 1.
Assertion: Zinc blende is concentrated by Froth floatation process.
Reason: Zinc blende is a sulphide ore.
(a) Assertion and Reason are correct, Reason explains the Assertion.
(b) Assertion is correct, Reason is wrong.
(c) Assertion is wrong, Reason is correct.
(d) Assertion and Reason are correct, Reason doesn’t explains Assertion.
Answer:
(a) Assertion and Reason are correct, Reason explains the Assertion.

Question 2.
Assertion: In thermite welding, aluminium powder and Fe₂O₃ are used.
Reason: Aluminium powder is a strong reducing agent.
(a) Assertion and Reason are correct, Reason explains the Assertion.
(b) Assertion is correct, Reason is wrong.
(c) Assertion is wrong, Reason is correct.
(d) Assertion and Reason are correct, Reason doesn’t explains Assertion.
Answer:
(a) Assertion and Reason are correct, Reason explains the Assertion.

Question 3.
Assertion: To design the body of an aircraft, aluminium alloys are used.
Reason: Aluminium becomes passive when it is treated with dil or con.HNO₃
(a) Assertion and Reason are correct, Reason explains the Assertion.
(b) Assertion is correct, Reason is wrong.
(c) Assertion is wrong, Reason is correct.
(d) Assertion and Reason are correct, Reason doesn’t explains Assertion.
Answer:
(d) Assertion and Reason are correct, Reason doesn’t explains Assertion.

Question 4.
Assertion: Tinstone and the impurity wolframite are seperated by magnetic separation.
Reason: Tinstone is magnetic and wolframite is non-magnetic in nature.
(a) Assertion and Reason are correct, Reason explains the Assertion.
(b) Assertion is correct, Reason is wrong.
(c) Assertion is wrong, Reason is correct.
(d) Assertion and Reason are correct, Reason doesn’t explains Assertion.
Answer:
(a) Assertion and Reason are correct, Reason explains the Assertion.

Question 5.
Assertion: Bauxite is purified by leaching.
Reason: Bauxite undergoes thermal decomposition.
(a) Assertion and Reason are correct, Reason explains the Assertion.
(b) Assertion is correct, Reason is wrong.
(c) Assertion is wrong, Reason is correct.
(d) Assertion and Reason are correct, Reason doesn’t explains Assertion.
Answer:
(b) Assertion is correct, Reason is wrong.

VI. Short answer questions:

Question 1.
State the modern periodic law.
Answer:
The physical and chemical properties of the elements are the periodic function of their atomic number.

Question 2.
‘X’ is a silvery white metal. X reacts with O₂ to form Y. The same compound is obtained from the metal on reaction with steam with the liberation of hydrogen gas. Identify X and Y.
Answer:
(i) Silvery white metal ‘X’ is Aluminium.
(ii) It reacts with O₂ to form ‘Y’

(iii) Y can also be obtained on reaction with steam with the liberation of H₂.

Question 3.
Write any four characteristics of periods.
Answer:

• In a period, the electrons are filled in the same valence shell of all elements.
• As the electronic configuration changes along the period, the chemical properties of the elements also change.
• The atomic size of the elements in a period decreases from left to right
• In a period, die metallic character of the element decreases, while their non-metallic character increases.

Question 4.
Write the Principle of Hydraulic washing.
Answer:
The difference in the densities or specific gravities of the ore and the gangue is the main principle behind this method.

Question 5.
What are coinage metals?
Answer:
Copper, silver and gold are called coinage metals, as they are used in making coins and jewellery.

Question 6.
How will you separate tinstone from wolframite?
Answer:
Magnetic separation method. Tinstone is magnetic in nature.
Method: The crushed ore is placed over a conveyer belt which rotates around two metal wheels, one of which is magnetic. The magnetic particles are attracted to the magnetic wheel and fall separately apart from the non¬magnetic particles.

Question 7.
What are ores?
Answer:
The mineral from which a metal can be readily and economically extracted on a large scale is said to be ore.
eg. Bauxite Al₂O₃.2H₂O is the ore of Aluminium

Question 8.
Define electronegativity.
Answer:
It is the tendency of an element in a covalent bond to attract the shared pair of electrons towards itself. It is a relative property.

Question 9.
In what period and group will an element with z = 118 will be present?
Answer:
Elements with z = 118 will be present in Period number ‘7’ and Group number 18.

Question 10.
Why flux is added during metallurgy?
Answer:
Flux is the substance added to the ore to reduce the fusion temperature and to remove impurities.
e.g. CaO, SiO₂

Question 11.
State the trends in the electronegativity in a Group and period.
Answer:
In a Group: Electronegativity decreases in a group because of the increased number of energy levels.
In a Period: The electronegativity increases because the increase in the nuclear charge.

Question 12.
Write a note about smelting.
Answer:
Smelting is a process of reducing the roasted metallic oxide to metal in a molten condition. In this process, impurities are removed by the addition of flux as slag.

Question 13.
Write the formula of the ores of Aluminium.
Answer:

Question 14.
Explain the action of Aluminium with air.
Answer:
On heating at 800°C, aluminium bums in the air very brightly forming its oxide and nitride.
4Al + 3O₂ → 2Al₂O₃ (Aluminium oxide)
2Al + N₂ → 2AlN (Aluminium nitride).

Question 15.
What happen when Aluminium reacts with steam?
Answer:
When steam is passed over red hot aluminium, H₂ gas is evolved.

Question 16.
Write the reaction of Aluminium with Sodium hydroxide?
Answer:

Question 17.
Explain the electrolytic refining of copper.
Answer:
Cathode: A thin plate of pure copper metal.
Anode: A block of impure copper metal.
Electrolyte: Copper sulphate solution + dilute H₂SO₄
When an electric current is passed through the electrolytic solution, pure copper gets deposited at the cathode and the impurities are settled at the bottom of the anode as anode mud.

Question 18.
Mention the uses of Aluminium.
Answer:
Aluminium is used in

1. household utensils
2. electrical cable industry
3. making aeroplanes and other industrial machine parts.

Question 19.
What are the methods employed to make an alloy?
Answer:

1. By fusing the metals together. Eg: Brass is made by melting zinc and copper.
2. By compressing finely divided metals. Eg: wood mexai.

Question 20.
Write the components of wood metal.
Answer:
Wood metal is an alloy of Lead, Tin, Bismuth and Cadmium.

Question 21.
What are the uses of copper?
Answer:

• Copper is used in manufacturing electric cables and other electric appliances.
• Copper is used for making utensils, containers, calorimeters and coins.
• Copper is used in electroplating.
• Copper is alloyed with gold and silver for making coins and jewels.

Question 22.
Give example for non-ferrous copper and aluminium alloys. Non-ferrous copper alloys: Brass (Cu, Zn), Bronze (Cu, Sn)
Answer:
Non-ferrous aluminium alloys: Duralumin (Al, Mg, Cu, Mn), Magnalium (Al, Mg)

Question 23.
How is rust formed?
Answer:
When iron is exposed to moist air, it forms a layer of brown hydrated Ferric oxide on its surface. This compound is known as rust.
4Fe + 3O₂ + xH₂O → 2Fe₂O₃. xH₂O (Rust).

Question 24.
Why are the alloys prepared?
Answer:

1. To modify appearance and colour.
2. To modify chemical activity.
3. To lower the melting point.
4. To increase hardness and tensile strength.
5. To increase resistance to electricity.

Question 25.
Define corrosion.
Answer:
Corrosion is the gradual destruction of metals by chemical or electrochemical reaction with the environment.

Question 26.
What are alloys? How are they prepared?
Answer:

• An alloy is a homogeneous mixture of a metal with other metals or with non-metals that are fused together. e.g. Brass is an alloy of zinc (solute) in copper (solvent)
• Alloys are prepared by fusing the metals together.
• Alloys are prepared by compressing finely divided metals one over the other.

Question 27.
Which is known as Wet corrosion or Electrochemical corrosion?
Answer:
The corrosive action in the presence of moisture is called wet corrosion. It occurs as a result of electrochemical reaction of metal with water or aqueous solution of salt or acids or bases.

Question 28.
Write a note on Cathodic protection.
Answer:
It is the method of controlling corrosion of a metal surface protected is coated with the metal which is easily corrodible. The easily corrodible metal is called Sacrificial metal to act as anode ensuring cathodic protection.

Question 29.
What are the methods used to prevent corrosion?
Answer:
Corrosion of metals is prevented

• by coating with paints
• by coating with oil and grease
• by alloying with other metals
• by the process of galvanization
• by electroplating
• by sacrificial protection

Question 30.
A reddish brown metal ‘A’ reacts with dil.HCl in the presence of O₂ and forms the compound ‘B’. ‘B’ can also be prepared by heating the metal A with Cl₂. Identify A and B.
Answer:
Reddish brown metal ‘A’ is copper.
(A) reacts with dil.HCl in the presence of O₂ and forms CuCl₂ which is ‘B’.

(B) can also prepared by the action of Cl₂.

Question 31.
Write the uses of copper.
Answer:

1. It is extensively used in manufacturing electric cables and other electric appliances.
2. It is used for making utensils, containers, calorimeters and coins.
3. It is used in electroplating.
4. It is alloyed with gold and silver for making coins and jewels.

Question 32.
Write the name and formula of the ores of iron.
Answer:

Question 33.
Define periodicity.
Answer:
The electronic configurations of elements help us to explain the periodic recurrence of physical and chemical properties. Anything which repeats itself after a regular interval is called periodic and this behaviour is called periodicity.

Question 34.
What happens in the combustion zone during the extraction of iron.
Answer:
The temperature in the combustion zone is 150°C. In this region coke bums 02 to form CO₂, when the charge comes in contact with a hot blast of air.

Question 35.
Explain the reactions taking place in the reduction zone.
Answer:
In the upper region of reduction zone, the temperature is at 400°C. In this region CO reduces ferric oxide to form spongy iron.

Question 36.
Define Metallic radius.
Answer:
It is defined as half the distance between the nuclei of adjacent metal atoms.

Question 37.
Complete the following reactions.

1. 4Fe + 10HNO₃ → 4Fe(NO₃)₂ + ………. + 3H₂O
2. 2Fe + 6H₂SO₄ → Fe₂(SO₄)₃ + ………. + 6H₂O

Answer:

1. NH₄NO₃
2. 3SO₂

Question 38.
What happens when steam is passed over red hot iron?
Answer:
When steam is passed over red hot iron magnetic oxide is formed.
3Fe + 4H₂O (steam) → Fe₃O₄ + 4H₂↑

Question 39.
Define Electron affinity.
Answer:
Electron affinity is the amount of energy released when a gaseous atom gains an electron to form its anion. It is also measured in kJ / mol.

Question 40.
Complete the table.
Answer:

Question 41.
Define Metallurgy.
Answer:
Metallurgy is a science of extracting metals from their ores and modifying the metals into alloys for various uses, based on their physical and chemical properties and their structural arrangement of atoms.

Question 42.
Write a short note on leaching or chemical process.
Answer:
This method is employed when the ore is in a very pure form. The ore is treated with a suitable reagent such that the ore is soluble in it but the impurities are not. The impurities are removed by filtration. The solution of the ore, ie., the filtrate is treated with a suitable reagent which precipitates the ore.
E.g. Bauxite Al₂O₃.2H₂O, the ore of aluminium.

Question 43.
Relate all the four columns of the table with their unique properties.
Answer:

Question 44.
Guess Who I am?
(i) I am preserved in Kerosene.
Answer:
Sodium

(ii) My ore is leached with NaOH.
Answer:
Aluminium

(iii) I sacrifice myself to protect my friend Iron.
Answer:
Magnesium

(iv) I am being used in propellers
Answer:
Nickel steel

Question 45.
Explain the method of making alloys.
Answer:

• By fusing the metals together. E.g. Brass is made by melting zinc and copper.
• By compressing finely divided metals. E.g. Wood metal: an alloy of lead, tin, bismuth and cadmium powder is a fusible alloy.

Question 46.
Write the differences between a mineral and a ore.
Answer:

VII. Long answer questions:

Question 1.
Write the reactions taking place during Bessemerisation of copper.
Answer:
2 FeS + 3O₂ → 2FeO + 2SO₂↑

2Cu₂S + 3O₂ → 2 Cu₂O + 2 SO₂↑
2Cu₂O + Cu₂S → 6 Cu + SO₂↑

Question 2.
How do electronegativity values help to find out the nature of bonding between atoms?
Answer:

• If the difference in electronegativity between two elements is 1.7, the bond has 50% ionic character and 50 % covalent character.
• If the difference is less than 1.7, the bond is considered to be covalent.
• If the difference is greater than 1.7, the bond is considered to be ionic.

Question 3.
Explain Froth floatation with diagram.
Answer:
Principle: This process depends on the preferential wettability of the ore with oil (pine oil) and the gangue particles by water. Lighter ores, such as sulphide ores, are concentrated by this method. Eg: Zinc blende (ZnS).

Question 4.
Explain the Baeyer’s process of conversion of Bauxite into alumina.
Answer:
(i) Bauxite ore is finely ground and heated under pressure with a solution of concentrated caustic soda solution at 150°C to obtain sodium meta aluminate.
(ii) On diluting sodium meta aluminate with water, a precipitate of aluminium hydroxide is formed.
(iii) The precipitate is filtered, washed, dried and ignited at 1000°C to get alumina.

Question 5.
Explain the Hall’s Process of electrolytic reduction of alumina with diagram.
Answer:
Hall’s Process:
Aluminium is produced by the electrolytic reduction of fused alumina (Al₂O₃) in the electrolytic cell.
Cathode : Iron tank linked with graphite
Anode : A bunch of graphite rods suspended in molten electrolyte.
Electrolyte : Pure alumina + molten cryolite + fluorspar (fluorspar lowers the fusion temperature of electrolyte)

Temperature: 900 – 950 °C
Voltage used: 5 – 6 V
Overall reaction: 2 Al₂O₃ → 4 Al + 3O₂↑

Question 6.
Write the reaction involved in the middle region of blast furnace during the extraction of iron.
Answer:
The Middle Region (Fusion Zone): The temperature prevails at 1000°C. In this region, CO₂ is reduced to CO.

Limestone decomposes to calcium oxide and CO₂.

These two reactions are endothermic due to absorption of heat. Calcium oxide combines with silica to form calcium silicate slag.
CaO + SiO₂ → CaSiO₃

Question 7.
What are the three different types of iron? Write their uses.
Answer:
(i) Pig iron (Iron with 2-4.5% of carbon): It is used in making pipes, stoves, radiators, railings, manhole covers and drain pipes.
(ii) Steel (Iron with < 0.25% of carbon): It is used in the construction of buildings, machinery, transmission cables and T. V towers and in making alloys.
(iii) Wrought iron (Iron with 0.25-2% of wraught carbon): It is used in making springs, anchors and electromagnets.

Question 8.
What is corrosion? Write the chemistry behind the formation of rust.
Answer:
(i) The slow and steady destruction of a metal by chemical or electro chemical reaction with the environment.
(ii) When the surface of iron is exposed to moisture and other gases present in the atmosphere, the following chemical reaction takes place.
Fe → Fe²⁺ + 2e^–
O₂ + 2H₂O + 4e^– → 4OH^–
O₂ + 4H⁺ + 4e^– → 2H₂O
The Fe²⁺ ions are oxidised to Fe³⁺ ions.
The Fe³⁺ ions combine OH^– ions to form Fe(OH)₃. This becomes rust which is hydrated ferric oxide with the formula Fe₂O₃.xH₂O. It is a reddish brown substance.

Question 9.
Explain the methods of preventing corrosion.
Answer:
(i) Alloying : The metals can be alloyed to prevent the process of corrosion. Eg: Stainless Steel

(ii) Surface Coating : It involves application of a protective coating over the metal. It is of the following types:
(a) Galvanization: It is the process of coating zinc on iron sheets by using electric current.
(b) Electroplating: It is a method of coating one metal over another metal by passing electric current.
(c) Anodizing: It is an electrochemical process that converts the metal surface into a decorative, durable and corrosion resistant. Aluminium is widely used for anodizing process.
(d) Cathodic Protection: It is the method of controlling corrosion of a metal surface protected is coated with the metal which is easily corrodible. The easily corrodible metal is called sacrificial metal to act as anode ensuring cathodic protection.

Question 10.
Discuss the main featured of Periods in the modern periodic table (or) long form of periodic table.
Answer:
The horizontal rows are called periods.There are seven periods in the periodic table.

1. First period (Atomic number 1 and 2): This is the shortest period. It contains only two elements (Hydrogen and Helium).
2. Second period (Atomic number 3 to 10): This is a short period. It contains eight elements (Lithium to Neon).
3. Third period (Atomic number 11 to 18): This is also a short period. It contains eight elements (Sodium to Argon).
4. Fourth period (Atomic number 19 to 36): This is a long period. It contains eighteen elements (Potassium to Krypton). This includes 8 normal elements and 10 transition elements.
5. Fifth period (Atomic number 37 to 54): This is also a long period. It contains 18 elements (Rubidium to Xenon). This includes 8 normal elements and 10 transition elements.
6. Sixth period (Atomic number 55 to 86): This is the longest period. It contains 32 elements (Caesium to Radon). This includes 8 normal elements, 10 transition elements and 14 inner transition elements (Lanthanides).
7. Seventh period (Atomic number 87 to 118): Like the sixth period, this period also accommodates 32 elements. Recently 4 elements have been included by IUPAC.

Question 11.
Discuss the main feature of Groups in the long form of periodic table.
Answer:
(i) The vertical columns in the periodic table starting from top to bottom are called groups. There are 18 groups in the periodic table.

(ii) Based on the common characteristics of elements in each group, they can be grouped as various families.

(iii) The Lanthanides and Actinides, which form part of Group 3 are called inner transition elements.

(iv) Except ‘group O’, all the elements present in each group have the same number of electrons in their valence shell and thus have the same valency. Eg: all the elements of group 1 have one electron in their valence shells (Is¹). So, the valency of all the alkali metals is ‘ 1’.

(v) As the elements present in a group have identical valence shell electronic configurations, they possess similar chemical properties.

(vi) The physical properties of the elements in a group such as melting point, boiling point and density vary gradually.

(vii) The atoms of the ‘group 0’ elements have stable electronic configuration in their valence shells and hence they are unreactive.

VIII. Hot Questions:

Question 1.
Why noble gases have zero electron affinity value?
Answer:
Noble gases show no tendency to accept electrons because the outers and p orbitals of noble gases are completely filled. No more electrons can be added to them and hence their electron affinities are zero.

Question 2.
Arrange the following ions in order of their increasing ionic radii.
Answer:
Li⁺, Mg²⁺, K⁺ Al³⁺
Al³⁺ < Li⁺ < Mg²⁺ < K⁺

Question 3.
Cationic radius is smaller than its corresponding neutral atom. Why?
Answer:
When a neutral atom lose one or more electrons it forms a cation.
Na → Na⁺ + e^–
The radius of this cation (r_Na+)is decreased than its parent atom (r_Na).
When an atom is charged to cation, the number of nuclear charges becomes greater than the number of orbital electrons. Florence the remaining electrons are more strongly attracted by the nucleus. Hence the cationic radius is smaller than its corresponding neutral atom.

Students can Download Samacheer Kalvi 10th Maths Model Question Paper 4 English Medium Pdf, Samacheer Kalvi 10th Maths Model Question Papers helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

Tamil Nadu Samacheer Kalvi 10th Maths Model Question Paper 4 English Medium

Instructions

• The question paper comprises of four parts.
• You are to attempt all the parts. An internal choice of questions is provided wherever applicable.
• All questions of Part I, II, III and IV are to be attempted separately.
• Question numbers 1 to 14 in Part I are Multiple Choice Quèstions of one-mark each. These are to be answered by choosing the most suitable answer from the given four alternatives and.writing the option code and the corresponding answer.
• Question numbers 15 to 28 in Part II àre two-marks questions. These are to be answered in about one or two sentences.
• Question numbers 29 to 42 in Part III are five-marks questions. These are to be answered in about three to five short sentences.
• Question numbers 43 to 44 in Part IV are eight-marks questions. These are to be answered in detail. Draw diagrams wherever necessary.

Time: 3 Hours
Maximum Marks: 100

PART – I

I. Choose the correct answer. Answer all the questions. [14 × 1 = 14]

Question 1.
If A = {1,2}, B = {1, 2, 3, 4}, C = {5,6} and D = {5, 6, 7, 8} then state which of the following statement is true ………….. .
(1) (A × C) ⊂ (B × D)
(2) (B × D) ⊂ (A × C)
(3) (A × B) ⊂ (A × D)
(4) (D × A) ⊂ (B × A)
Answer:
(1) (A × C) ⊂ (B × D)

Question 2.
If f(x) = 2x² and g(x) = \(\frac { 1 }{ 3x }\), then jog is ………….. .
(1) \(\frac{3}{2 x^{2}}\)
(2) \(\frac{2}{3 x^{2}}\)
(3) \(\frac{2}{9 x^{2}}\)
(4) \(\frac{1}{6 x^{2}}\)
Answer:
(3) \(\frac{2}{9 x^{2}}\)

Question 3.
Given F₁ = 1,F₂ = 3 and F_n = F_n-1 + F_n-2  then F₅ is ………….. .
(1) 3
(2) 5
(3) 8
(4) 11
Answer:
(4) 11

Question 4.
The value of (1³ + 2³ + 3³ +. . . .+ 15³) – (1 + 2 + 3 +….+ 15) is ………….. .
(1) 14400
(2) 14200
(3) 14280
(4) 14520
Answer:
(3) 14280

Question 5.
The solution of the system x + y – 3z = -6 , – 7y + 7z = 7, 3z = 9 is ………….. .
(1) x = 1, y = 2, z = 3
(2) x = -1, y = 2, z = 3
(3) x = -1, y = -2, z = 3
(4) x = 1, y = 2, z = 3
Answer:
(1) x = 1, y = 2, z = 3

Question 6.
If number of columns and rows are not equal in a matrix then it is said to be a ………….. .
(1) diagonal matrix
(2) rectangular matrix
(3) square matrix
(4) identity matrix
Answer:
(2) rectangular matrix

Question 7.
The slope of the line which is perpendicular to a line joining the points (0, 0) and (-8, 8) is ………….. .
(1) -1
(2) 1
(3) \(\frac { 1 }{ 3 }\)
(4) -8
Answer:
(2) 1

Question 8.
If sin θ + cos θ = a and sec θ + cosec θ = 6, then the value of b (a² – 1} is equal to ………….. .
(1) 2 a
(2) 3 a
(3) 0
(4) 2 ab
Answer:
(1) 2 a

Question 9.
If two solid hemispheres of same base radius r units are joined together along their bases, then curved surface area of this new solid is ………….. .
(1) 4π r² sq. units
(2) 6π r² sq. units
(3) 3π r² sq. units
(4) 8π r² sq. units
Answer:
(1) 4π r² sq. units

Question 10.
The standard deviation of a data is 3. If each value is multiplied by 5 then the new variance is ………….. .
(1) 3
(2) 15
(3) 5
(4) 225
Answer:
(4) 225

Question 11.
Kamalam went to play a lucky draw contest. 135 tickets of the lucky draw were sold. If the probability of Kamalam winning is \(\frac { 1 }{ 9 }\), then the number of tickets bought by Kamalam is ………….. .
(1) 5
(2) 10
(3) 15
(4) 20
Answer:
(3) 15

Question 12.
If α and β are the zeros of the polynomial p(x) = 4x² + 3x + 7 then \(\frac{1}{\alpha}+\frac{1}{\beta}\) is equal to …… .
(1) \(\frac{7}{3}\)
(2) \(-\frac{7}{3}\)
(3) \(\frac{3}{7}\)
(4) \(-\frac{3}{7}\)
Answer:
(4) \(-\frac{3}{7}\)

Question 13.
The common ratio of the G.P. a^m-n, a^m, a^{m + n} is ………….. .
(1) a^m
(2) a^-m
(3) aⁿ
(4) aⁿ
Answer:
(3) aⁿ

Question 14.
If the circumference at the base of a right circular cone and the slant height are 120π cm and 10 cm respectively, then the curved surface area of the cone is equal to ………….. .
(1) 1200 π cm²
(2) 600 π cm²
(3) 300 π cm²
(4) 600 π m²
Answer:
(2) 600 π cm²

PART – II

II. Answer any ten questions. Question No. 28 is compulsory. [10 × 2 = 20]

Question 15.
Let A = {1,2, 3, 4} and B = N . Let f: A → B be defined by f(x) = x³ then,
(i) find the range of f
(ii) identify the type of function
Answer:
A = {1,2,3,4}
B = (1,2,3,4,5, ………}
f(x) = x³
f(1) = 1³ = 1
f(2) = 2³ = 8
f(3) = 3³ = 27
f(4) = 4³ = 64
(i) Range = {1, 8,27, 64)
(ii) one -one and into function.

Question 16.
If f(x) = 2x -1, g (x) = \(\frac{x+1}{2}\), show that fog = gof = x
Answer:
f(x) = 2x – 1 : g(x) = \(\frac{x+1}{2}\)
fog = f[g(x)]
= \(f\left[\frac{x+1}{2}\right]\)
= \(2\left(\frac{x+1}{2}\right)-1\)
= x + 1 – 1
= x

gof = g[f(x)]
= g (2x – 1)
= \(\frac{2 x-1+1}{2}\)
= \(\frac{2 x}{2}\)
= x
∴ fog = gof = x
Hence it is proved.

Question 17.
Determine the general term of an A.P. whose 7^th term is -1 and 16^th term is 17.
Answer:
Let the AP. be t₁, t₂, t₃, t₄, ………
It is given that t₇ = -1 and t₁₆ = 17
a + (7 – 1)d = -1 and a + (16 – 1) d = 17
a + 6d = – 1 ……. (1)
a + 15d = 17 ……… (2)
Subtracting equation (1) from equation (2), we get 9d = 18 ⇒ d = 2
Putting d = 2 in equation (1), we get a + 12 = -1 So, a = -13
Hence, general term t_n = a + (n – 1) d = -13 + (n – 1) × 2 = 2n – 15

Question 18.
Find x so that x + 6, x + 12 and x + 15 are consecutive terms of a Geometric Progression.
Answer:
\(\frac{t_{2}}{t_{1}}=\frac{x+12}{x+6}\), \(\frac{t_{3}}{t_{2}}=\frac{x+15}{x+12}\)
Since it is a G.P.
\(\frac{x+12}{x+6}=\frac{x+15}{x+12}\)
(x + 12)² = (x + 6) (x + 15)
x² + 24x + 144 = x² + 21x + 90
3x = -54 ⇒ x = \(\frac{-54}{3}\) = – 18

Question 19.
Find the excluded values of the expression \(\frac{x^{2}+6 x+8}{x^{2}+x-2}\)
Answer:
x² + 6x + 8 = (x + 4)(x + 2)
x² + x – 2 = (x + 2)(x – 1)


The expression \(\frac{x+4}{x-1}\) is undefined
when x – 1 = 0 ⇒ x = 1
The excluded value is 1

Question 20.
Solve 3p² + 2√5p – 5 = 0 by formula method.
Answer:
Compute 3p² + 2√5p – 5 = 0 with the standard form ax² + bx + c = O
a = 3, b = 2√5, c = -5
p = \(\frac{-b \pm \sqrt{b^{2}-4 a c}}{2 a}\)
Substituting the values of a, b and e in the formula we get,

Therefore, x = \(\frac{\sqrt{5}}{3},-\sqrt{5}\)

Question 21.
Write the expression \(\frac{\alpha+3}{\beta}+\frac{\beta+3}{\alpha}\) in terms of α + β and αβ.
Answer:

Question 22.
Rhombus PQRB is inscribed in ∆ABC such that ∠B is one of its angle. P, Q and R lie on AB, AC and BC respectively. If AB = 12 cm and BC = 6 cm, find the sides PQ, RB of the rhombus.
Answer:
Let the side of the rhombus be “x”. Since PQRB is a Rhombus PQ || BC
By basic proportionality theorem
\(\frac{A P}{A B}=\frac{P Q}{B C} \Rightarrow \frac{12-x}{12}=\frac{x}{6}\)
12x = 6(12 – x)
12x = 72 – 6x
12x + 6x = 72
18x = 72 ⇒ x = \(\frac { 72 }{ 18 }\) = 4
Side of a rhombus = 4cm
PQ = RB = 4cm

Question 23.
Find the equation of a straight line which is parallel to the line 3x – 7y = 12 and passing through the point (6,4)
Answer:
Equation of the straight line, parallel to 3x – 7y – 12 = 0 is 3x – 7y + k= O
Since it passes through the point (6,4)
3(6) – 7(4) + k = 0
k = 28 – 18= 10
Therefore, equation of the required straight line is 3x – 7y + 10 = 0.

Question 24.
Prove that \(\frac{\tan ^{2} \theta-1}{\tan ^{2} \theta+1}\) = 1 – 2 cos² θ
Answer:

= sin² θ – cos² θ = 1 – cos² θ – cos² θ
= 1 – 2 cos²θ
L.H.S = R.H.S
Hence it is proved.

Question 25.
The standard deviation and coefficient of variation of a data are 1.2 and 25.6 respectively. Find the value of mean.
Answer:
Standard deviation (σ) = 1.2
Coefficient of variation = 25.6
\(\frac{\sigma}{x} \times 100\) = 25.6
\(\frac{1.2}{\bar{x}} \times 100\) = 25.6 ⇒ 25.6 × x̄ = 1.2 × 100
x̄ = \(\frac{120}{25.6}=\frac{120 \times 10}{256}\) = 4.687 = 4.69
Value of mean = 4.69

Question 26.
Three dice are thrown simultaneously. Find the probability of getting the same number.
Answer:
Sample space = {(1, 1, 1) (1, 1,2) (1, 1,3). .. . (6,6, 6)}
n(S) = 216
Let A be the event of getting the same number on all the three dice
A = {(1,1,1),(2,2,2),(3,3,3),(4,4,4)(5,5,5)(6,6,6fl
n(A) = 6
P(A) = \(\frac{n(\mathrm{A})}{n(\mathrm{S})}=\frac{6}{216}=\frac{1}{36}\)

Question 27.
If the curved surface area of a solid hemisphere is 2772 sq. cm, then find its total surface area.
Answer:
Curved surface area ofa hemisphere = 2772 sq.cm
2πr² = 2772
πr² = \(\frac{2772}{2}\) = 1386
T.S.A of the hemisphere = 3πr² sq. units
= 3 × 1386 cm²
= 4158 cm²

Question 28.
Which term of the geometric sequence 5,2, \(\frac{4}{5}, \frac{8}{25} \cdots \text { is } \frac{128}{15625}\) ?
Answer:
The given G.P is 5,2, \(\frac{4}{5}, \frac{8}{25} \cdots \text { is } \frac{128}{15625}\)
Here a = 5, r = \(\frac { 2 }{ 5 }\)
t_n = \(\frac{128}{15625}\)
a.r_n-a = \(\frac{128}{15625}\)

PART – III

III. Answer any ten questions. Question No. 42 is compulsory. [10 × 5 = 50]

Question 29.
Let f: A → B be a function defined by f(x) = \(\frac { x }{ 2 }\) – 1, where A = {2,4,6,10,12}, B = {0,1,2,4,5,9} . Represent f by
(i) set of ordered pairs
(ii) a table
(iii) an arrow diagram
(iv) a graph
Answer:
(i) f = {(2,0)(4, 1)(6,2)(10,4)(12,5)

(ii)

(iii)

(iv)

Question 30.
Given f(x) = x – 1, g(x) = 3x + 1 and h(x) = x² show that (fog)oh = fo(goh)

Question 31.
The product of three consecutive terms of a Geometric Progression is 343 and their sum is \(\frac{91}{3}\) Find the three terms.

Question 32.
Find the sum of all natural numbers between 602 and 902 which are not divisible by 4?

Question 33.
There are 12 pieces of five, ten and twenty rupee currencies whose total value is ₹105. But when first 2 sorts are interchanged in their numbers its value will be increased by ₹20. Find the number of currencies in each sort.

Question 34.
A passenger train takes 1 hr more than an express train to travel a distance of 240 km from Chennai to Virudhachalam. The speed of passenger train is less than that of an express train by 20 km per hour. Find the average speed of both the trains.

Question 35.
ABCD is a trapezium in which AB || DC and P,Q are points on AD and BC respectively, such that PQ || DC if PD = 18 cm, BQ = 35 cm and QC = 15 cm, find AD.

Question 36.
Find the equation of the perpendicular bisector of the line joining the points A(-4,2) and B(6, -4).

Question 37.
From the top of a tower 50 m high, the angles of depression of the top and bottom of a tree and observed to be 30° and 45° respectively. Find the height of the tree. ( √3 = 1.732)

Question 38.
A hemispherical bowl is filled to the brim with juice. The juice is poured into a cylindrical vessel whose radius is 50% more than its height. If the diameter is same for both the bowl and the cylinder then find the percentage of juice that can be transferred from the bowl into the cylindrical 1 vessel.

Question 39.
A box contains cards numbered 3, 5, 7,9,… 35,37. A card is drawn at random from the box. Find the probability that the drawn card have either multiples of 7 or a prime number.

Question 40.
The function f: [-7, 6] → R is defined as follows.

Question 41.
The denominator of a fraction is 4 more than twice the numerator. When both the numerator and denominator are decreased by 6, then the denominator becomes 12 times the numerator determine the fraction.

Question 42.
If for distribution Σx – 7 = 3 ; (Σx – 7)² = 57 and total number of the item is 20; find the mean and standard deviation.

PART – IV

IV. Answer all the questions. [2 × 8 = 16]

Question 43.
(a) Draw a circle of diameter 6 cm from a point P, which is 8 cm away from its centre. Draw the two tangents PA and PB to the circle and measure their lengths.

[OR]

(b) Construct a triangle ∆PQR such that QR = 5 cm, ∠P = 30° and the altitude from P to QR is of length 4.2 cm.

Question 44.
(a) Draw the graph of y = x² and hence solve x² – 4x – 5 = 0.

[OR]

(b) Draw the graph of y = x² + 3x + 2 and use it to solve the equation x² + 2x + 4 = 0.