Write the equations involved in the preparation of nitric acid by Ostwalld's process by maintaining the reaction conditions.

Explanation

In this method, nitric acid is prepared by catalytic oxidation of ammonia by atmospheric oxygen.
`4NH_(3)(g)+5O_(2)(g)overset("Pt/Rh catalyst")underset("500 K, 9 bar")rarr 4NO(g)+6H_(2)O(g)`
Nitric oxide `(NO)` formed will combine with oxygen to form `NO_(2)`
`2NO(g)+O_(2)(g)hArr 2NO_(2)(g)`
Nitric oxide formed dissolves in water to form nitric acid.
`3NO_(2)(g)+H_(2)O(g)rarr2HNO_(3)(aq)+NO(g)`
The Nitric Oxide thus formed is recycled and the aqueous `HNO_(3)` can be concentrated by distillation to give `68%` by mass. Further concentration to `98%` can be achieved by dehydration with concentrated `H_(2)SO_(4)`.