A gas 'A' reacts with another gas 'B' in the presence of a catalyst to give a colourless gas 'C'. The gas 'C' when comes in contact with air produces a brown gas 'D'. The solution of 'A' in water turns red litmus blue. Explain the observations.

Write the equation for the action of heat on:

(a) Ammonium chloride

(b) Ammonium nitrate

State whether each reaction is an example of thermal decomposition or thermal dissociation.

(i) Name the common refrigerant. How does it deplete ozone layer?

(ii) What is the alternative of chlorofluorocarbon carbon?

(iii) State the advantages and disadvantages of using ammonia as refrigerant?

(a) Which feature of ammonia molecule leads to the formation of the ammonium ion when ammonia dissolves in water?

(b) Name the other ion formed when ammonia dissolves in water.

(c) Give one test that can be used to detect the presence of the ion produced in (b).