(i) How is HNO3 prepared commercially?(ii) Write chemical equation of

1.	(i) How is HNO3 prepared commercially?(ii) Write chemical equation of the reactions involved.(iii) What concentration by mass of HNO3 can be obtained?(iv) Give any two uses of HNO3.
Answer» (i) On a large scale, it is prepared mainly by Ostwald’s process. This method is based upon catalytic oxidation of NH₃ by atmospheric oxygen. (ii) 4NH₃(g) + 5NO₂(g) \(\underset{9 bar}{\stackrel{Pt,500K}{\rightarrow}} \) 4NO(g) + 6H₂O(l) 2NO(g) + O₂ → 2NO₂ (g) 3NO₂ (g) + H₂O(l) → 2HNO₃ (aq) + NO(g) (iii) 68% by mass, (iv) (a) It is used in the manufacture fertilizers, explosives. (b) It is used as lab regent.

(i) How is HNO3 prepared commercially?(ii) Write chemical equation of the reactions involved.(iii) What concentration by mass of HNO3 can be obtained?(iv) Give any two uses of HNO3.

Answer»

(i) On a large scale, it is prepared mainly by Ostwald’s process. This method is based upon catalytic oxidation of NH₃ by atmospheric oxygen.

(ii) 4NH₃(g) + 5NO₂(g) \(\underset{9 bar}{\stackrel{Pt,500K}{\rightarrow}} \) 4NO(g) + 6H₂O(l)

2NO(g) + O₂ → 2NO₂ (g)

3NO₂ (g) + H₂O(l) → 2HNO₃ (aq) + NO(g)

(iii) 68% by mass,

(iv) (a) It is used in the manufacture fertilizers, explosives.

(b) It is used as lab regent.