(a) Sodium hydroxide - (i) it is used in de-greasing metals. (ii) it is involved in the production of soaps and detergents.

(b) Chlorine (i) It is used in the production of bleaching powder. (ii) It is used in the production of hydrochloric acid.

(c) Hydrogen: (i) It is used in the production of hydrochloric acid. (ii) It is used in the hydrogenation of oils.

(d) Hydrochloric acid: (i) It is used in medicines and cosmetics.