Question

Nitric acid can be obtained from ammonia via the formations of the intermediate compounds:

• A. nitric oxide and nitrogen dioxide
• B. nitrogen and nitric oxide
• C. nitric oxide and dinitrogen pentoxide
• D. nitrogen and nitrous oxide

Answer 1

Answer: (A)

Ostwald process for the manufacture of nitric acid:

$\underset{\text{Ammonia}}{4{NH}_3}+{5O}_2\underset{700-{800}^{o}C}{\overset{Pt\text{gauge}}{\to }}\underset{\text{Nitric oxide}}{4NO}+6H_{2}O;\Delta H=-21.5kcal$

$2NO+O_2\underset{}{\overset{{50}^{o}C}{\to }}\underset{\text{Nitrogen dioxide}}{2{NO}_2}$

$4{NO}_2+2H_{2}O+O_2⟶\underset{\text{Nitric acid}}{4H{NO}_3}$