The following questions are pertaining to the laboratory preparation of hydrochloric acid.

(a) Name the reactants used during the laboratory preparation of hydrochloric acid.

(b) Give suitable reason for choosing the reactants for laboratory preparation.

(c) Write balanced chemical equation for the reaction taking place below 200°C.

Give reasons

(a) Liquid ammonia is used as a refrigerant in ice plants.

(b) Only all-glass apparatus should be used for the preparation of nitric acid by heating concentrated sulphuric acid and potassium nitrate.

(c) A piece of wood becomes black when concentrated sulphuric acid is poured on it.

(a) Write the cell reaction for the electrolysis of dil. AgNO₃ solution using Ag anode and Cu cathode.

(b) Name a compound of ammonia which sublimes on heating?

(c) Name the gas evolved on reaction of aluminium with boiling concentrated caustic alkali solution, write the equation.

(a) A compound X having vinegar like smell when treated with ethanol in the presence of the acid, Z, gives a compound Y which has a fruity smell.

The reaction is

$\text{C}$2\text{H}5\text{OH} + \text{X} \xrightarrow{\text{Z}} \text{Y} + \text{H}_2\text{O}

1. Identify X, Y and Z.
2. Name the above reaction.

(b) Name the element in period 3 whose affinity is zero.