1. Bleaching powder is used as a disinfectant for water to:

2. Copper sulphate crystals when heated strongly, lose their water of crystallization
to give anhydrous copper sulphate accompanied by a change in color from:

3. The sample of soil from a particular place was tested for its pH value. It came out
to be 5. Which one of the following should be added to the soil to make it suitable for
the plant growth?

i. Calcium chloride
ii. Calcium Hydroxide
iii. Calcium oxide
Choose the correct option:

4. An ant’s sting can be treated with …………which will neutralise the effect of the
chemical injected by the ant’s sting into our skin.
Choose the correct option from the following to be filled in the blank space:

5. Which of the following indicators turn red in an acidic solution?

i. Phenolphthalein
ii. Litmus
iii. Turmeric
iv. Methyl orange
Choose the correct option:

6. Dilute acid does not produce carbon dioxide on being treated with:

7. The figure given below represents the experiment carried out between conc.
sulphuric acid and sodium chloride, which react with each other to form HCl gas.

Blue litmus paper is brought near the mouth of the delivery tube to check the presence of
HCl acid but no change is observed in the color of litmus paper because:

8. Zinc granules on treating with an acid X, form the zinc sulphate (ZnSO4) salt along
with the evolution of a gas Y which burns with a pop sound when brought near to a
burning candle. Identify the acid X and gas evolved Y

9. Some fruits like mango, lemon, raw grapes, orange, etc., have a sour taste due to
the presence of:

10. Which of the following phenomena occur, when a small amount of acid is added to
water?
i. Ionisation
ii. Neutralisation
iii. Dilution
iv. Salt formation

11. What is formed when zinc reacts with sodium hydroxide?

12. Rain is called acid rain when its:

13. Chemical formula of washing soda is

14. Tomato is a natural source of which acid?

15. When hydrogen chloride gas is prepared on a humid day, the gas is usually passed through the guard tube containing calcium chloride. The role of calcium chloride taken in the guard tube is to

16. When a base reacts with a metal, it forms a salt and hydrogen gas is released. By what method can the presence of hydrogen be detected?

17. An aqueous solution turns the red litmus solution blue. Excess addition of which of the following solutions would reverse the change?

18. Farmers neutralize the effect of Acidity on soil by adding

19. Which one of the following can be used as an acid-base indicator by a visually impaired student ?

20. A substance ‘A’ does not dissociate completely into its ions in aqueous solutions. It is bitter in taste and soapy to touch.Identify the substance A.