Consider the following experimental set-up.
(i) Identify by name: P; Q; R; S and T.
(ii) State the method of collection of gas, S.
(iii) What is the function of R in the experimental set-up?
(iv) Write the balanced equation of the reaction for the preparation of gas S.
Explanation
(i) P - Delivery tube
Q - Drying tower
R - Calcium oxide
S - Ammonia gas
T - Retort stand with clamp
(ii) Upward delivery of gas/downward displacement of air
(iii) To dry the gas
(iv) Ca(OH)\(_{2(aq)}\) + 2NH\(_4\)Cl\(_{(aq)}\) \(\to\) CaCl\(_{2(aq)}\) + 2H\(_2\)O\(_{(l)}\) + 2NH\(_{3(g)}\)