The composition of air in terms of percentage of its varous components is given.
(a) Identify X and Y.
(b) Mention any two uses of X and Y .
(c ) identify the gases present in Z.

Explanation

(a) X is nitrogen and Y is oxygen.
(b) (i) Nitrogen dilutes the activity of oxygen.
(ii) Nitrogen is essential for the growth of plants.
(iii) Oxygen is essential for respiration.
(iv) Oxygen support combustion.
(c ) Z contains carbon dioxide , argon , helium , water vapour.