How is nitric acid manufactured by Ostwald's process ?

Explanation

Ostwald.s process :
Step (1) : A mixture of ammonia and excess of atmospheric oxygen `(1:10)` is passed through a tower containing pt/Rh guaze catalyst maintained at 500 K temperature and 9 bar pressure. Then catalytic oxidation of `NH_(3)` takes place, forming Nitric oxide.
`4NH_(3 (g)) + 5O_(2 (g)) underset("500 K, 9bar") overset("pt/Rh gauge catalysst") (to) 4NO_("(g)") + 6H_(2) O_("(g)")`
Step (2) : The nitric oxide thus obtained is made to combine with oxygen. Then `NO_2` is obtained.
`2NO_("(g)") + O_(2) (g) hArr 2NO_(2(g))`
Step (3) : The nitrogen dioxide, is dissolved in water to give nitric acid
`3NO_(2) (g) + H_(2) O_((i)) to 2HNO_(3) (aq) + NO(g)`
The NO formed is recycled.