1. Which of the following gases can be used for storage

2. Give the ratio in which hydrogen and oxygen are present in water by volume.

3. Electrolysis of water is a decomposition reaction. The mole ratio of hydrogen and oxygen gases liberated during electrolysis of water is:

4. In which of the following chemical equations, the abbreviations represent the correct states of the reactants and products involved at reaction temperature?

5. When green coloured ferrous sulphate crystals are heated, the colour of the crystal changes because

6. When Ag is exposed to air it gets a black coating of

7. Which of the following is an endothermic process?

8. When S02 gas is passed through saturated solution of H2S, which of the following reaction occurs?

9. Oxidation is a process which involves

10. Which among the following statement(s) is (are) true. Exposure of silver chloride to sunlight for a long duration turns grey due to (i) the formation of silver by decomposition of silver chloride (ii) sublimation of silver chloride (iii decomposition of chlorine gas from silver chloride (iv) oxidation of silver chloride

11. The condition produced by aerial oxidation of fats and oils in foods marked by unpleasant smell and taste is called:

12. Which of the following is an endothermic process?

13. A substance added to food containing fats and oils is called:

14. In the double displacement reaction between aqueous potassium iodide and aqueous lead nitrate, a yellow precipitate of lead iodide is formed. While performing the activity if lead nitrate is not available, which of the following can be used in place of lead nitrate?

15. In the double displacement reaction between aqueous potassium iodide and aqueous lead nitrate, a yellow precipitate of lead iodide is formed. While performing the activity if lead nitrate is not available, which of the following can be used in place of lead nitrate?

16. The process of reduction involves

17. Give the ratio in which hydrogen and oxygen are present in water by volume.

18. When green coloured ferrous sulphate crystals are heated, the colour of the crystal changes because

19. Three beakers labelled as A, B and C each containing 25 ml of water were taken. A small amount of NaOH, anhydrous CuSO₄ and NaCl were added to the beakers A, B and C respectively. It was observed that there was an increase in the temperature of the solution contained in beakers A and B, whereas in case of beaker C, the temperature of the solution falls. Which one of the following statement(s) is (are) correct? (i) In beakers A and B, exothermic process has occurred. (ii) In beakers A and B, endothermic process has occuBftd. (iii) In beaker C exothermic process has occurred. (iv) In beaker C endothermic process has occurred.

20. Which of the following statements about the given reaction are correct. 3Fe (s) + 4H₂O (g) → Fe₃O₄ (s) + 4 H₂ (g) (i) Iron metal is getting oxidised (ii) Water is getting reduced (iii) Water is acting as reducing agent (iv) Water is acting as oxidising agent