Question

A non-metal X which is the largest constituent of air combines with hydrogen when heated in the presence of iron as catalyst to form a gas Y. When gas Y is treated with sulphuric acid, it forms a compound Z which is used as a chemical fertiliser.

(a) What are X, Y and Z?
(b) To which group of periodic table does X belong?
(c) Name the periodic table in which X is placed.
(d) Which element is placed just before X in the period?
(e) Which element is placed just after X in the period?

Answer 1

(a) Element X is Nitrogen gas (N₂) since the largest constituent of air is nitrogen. When nitrogen reacts with hydrogen in the presence of iron as a catalyst, ammonia (NH₃) is formed. Therefore, Y is ammonia (NH₃). When ammonia reacts with sulpuric acid, ammonium sulphate is formed which is used as a chemical fertilizer. Therefore, Z is ammonium sulphate (NH₄)₂SO₄.

(b) Nitrogen belongs to group 15 of the periodic table.

(c) Nitrogen is placed in the second period of the periodic table.

(d) Carbon (C) is placed just before nitrogen in the period.

(e) Oxygen (O) is placed just after nitrogen in the period.