DPP-10S13

DECOMPOSITION REACTION

1. Why is the amount of gas collected in one of the test tubes in the Electrolysis of water is double of the amount collected in the other? Name this gas.

2. Why are decomposition reactions called the opposite of combination reactions? Write equations to explain. (CBSE 2012)

3. 2g of silver chloride is taken in a china dish and the china dish is placed in sunlight for sometime. What will be your observation in this case? Write the chemical reaction involved in the form of a balanced chemical equation. Identify the type of chemical reaction.

4. (A) Write two observations when lead nitrate is heated in a test tube.

(B) Name the type of reaction.

5. Hydrated ferrous sulphate crystals are heated in a boiling tube for a few seconds. Water droplets are seen in the inner sides

(A) What is the colour of the crystals before and after mild heating?

(B) Identify gas X and the residue Y formed.