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1. In the following experimental setup of electrolysis of water, if P and Q are the gases collected in the test tubes enclosing the electrodes R and S, then select the option/options in which the matching is correct:


(i) P- Oxygen gas , R-Anode

(ii) P- Hydrogen gas , R-Cathode

(iii) Q-Hydrogen gas , S-Cathode

(iv) Q-Oxygen gas , S-Anode

A. (i) and (ii) B. (iii) and (iv) C. (i) and (iii) D. (ii) and (iv)

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2. You have three aqueous solutions A, B and C as given below:

A - Potassium nitrate

B - Ammonium chloride

C - Sodium carbonate

The ascending order of the pH of these solutions is:

A. A < B < C B. B < C < A C. C < A < B D. B < A < C

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3. Select from the following a statement which is not true about burning of magnesium ribbon in air:

A. It burns with a dazzling white flame. B. A white powder is formed on burning. C. It is an endothermic reaction. D. It is an example of a combination reaction.

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4. A Hydrocarbon which does not belong to the same homologous series of carbon compounds is

A. C₄H₁₀ B. C₆H₁₄ C. C₇H₁₄ D. C₁₀H₂₂

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5. The colour of the solution observed after about 1 hour of placing iron nails in copper sulphate solution is

A. Blue B. Pale green C. Yellow D. Reddish brown

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6. Juice of tamarind turns blue litmus to red. It is because of the presence of a chemical compound called

A. Acetic acid B. Methanoic acid C. Oxalic acid D. Tartaric acid

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7. The water of crystallization is present in

(i) Bleaching Powder

(ii) Plaster of Paris

(iii) Washing Soda

(iv) Baking Soda

A. (ii) and (iv) B. (ii) and (iii) C. (i) and (iii) D. (i) and (iv)

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8. A tall pea plant with round seeds (TTRR) is crossed with a short pea plant with wrinkled seeds (ttrr). The F1 generation will be

A. 25% tall with round seeds B. 50% tall with wrinkled seeds C. 75% tall with wrinkled seeds D. 100% tall with round seeds

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9. A pair of endocrine glands located in the human brain is

A. Parathyroid and Pituitary B. Pineal and Thymus C. Hypothalamus and Thymus D. Hypothalamus and Pineal

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10. Select the option having correct matching of the organism given in Column I with the mode of reproduction in Column II:

A. P-4, Q-2, R-1, S-3 B. P-3, Q-4, R-5, S-2 C. P-3, Q-4, R-1, S-2 D. P-4, Q-3, R-2, S-1

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11. The basic filtration unit of the excretory system in human beings is:

A. Nephron B. Urethra C. Neuron D. Urinary bladder

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12. In human alimentary canal, the digestive juice secreted by the gastric glands are

A. Bile, Trypsin, Pepsin B. Hydrochloric acid, Pepsin, Mucus C. Lipase, Bile, Mucus D. Salivary amylase, Pepsin, Bile

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13. Identify from the following the ray diagram which shows the correct path of the reflected ray for the ray incident on a concave mirror as shown:

A. B. C. D.

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14. The part of human eye which controls the amount of light entering into it.

A. Iris B. Cornea C. Ciliary muscles D. Pupil

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15. Consider the following food chain:
Grass → Grasshopper → Frog → Snake → Eagle
If the amount of energy available at third trophic level is 50 kJ, the available energy at the producer level was:

A. 0.5 kJ B. 5 kJ C. 500 kJ D. 5000 kJ

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16. The incorrect statement about ozone is

A. It is a deadly poisonous gas. B. It shields the surface of the earth from UV radiation from sun. C. It is used as a refrigerant and in fire-extinguishers. D. It is formed by combining oxygen molecule with free oxygen atom.

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17. Assertion (A): Carbon and its compounds are our major sources of fuels.
Reason (R): Most of the carbon compounds on burning release a large amount of heat and light.

A. Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A). B. Both Assertion (A) and Reason (R) are true and Reason (R) is not the correct explanation of the Assertion (A). C. Assertion (A) is true, but Reason (R) is false. D. Assertion (A) is false, but Reason (R) is true.

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18. Assertion (A): Xylem tissue moves water and minerals obtained from the soil by the roots.
Reason (R): Xylem tissue is found only in the roots of a plant.

A. Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A). B. Both Assertion (A) and Reason (R) are true and Reason (R) is not the correct explanation of the Assertion (A). C. Assertion (A) is true, but Reason (R) is false. D. Assertion (A) is false, but Reason (R) is true.

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19. Assertion (A): In the common domestic circuits the earth wire is connected to a metallic plate buried deep inside the earth.
Reason (R): Earth wire ensures that any leakage of current to the metallic body of the appliance keeps its potential to that of the earth, so the user may not get a severe electric shock.

A. Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A). B. Both Assertion (A) and Reason (R) are true and Reason (R) is not the correct explanation of the Assertion (A). C. Assertion (A) is true, but Reason (R) is false. D. Assertion (A) is false, but Reason (R) is true.

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20. Assertion (A): Food web is a network of several food chains operating in an ecosystem.
Reason (R): Food web decreases the stability of an ecosystem.

A. Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A). B. Both Assertion (A) and Reason (R) are true and Reason (R) is not the correct explanation of the Assertion (A). C. Assertion (A) is true, but Reason (R) is false. D. Assertion (A) is false, but Reason (R) is true.