Question

The steps for the manufacture of nitric acid by Ostwald process are given. Arrange them in sequence.
(a) Recirculation of nitric oxide
(b) Addition of $H_{2}O$ to nitrogen dioxide
(c) Oxidation of nitric oxide
(d) Catalytic oxidation of ammonia

• A. d c b a
• B. d c a b
• C. c d b a
• D. c d a b

Answer 1

Answer: (A)

d c b a

In ostwald process Ammonia is converted to nitric acid in 2 stages. It is oxidized (in a sense "burnt") by heating with oxygen in the presence of a catalyst to form nitric oxide and water. Nitric oxide is oxidized again to yield nitrogen dioxide. This gas is then readily absorbed by the water and forms nitric acid. Thus the steps of process are :
(d) Catalytic oxidation of ammonia
(c) Oxidation of nitric oxide
(b) Addition of $H_{2}O$ to nitrogen dioxide
(a) Recirculation of nitric oxide