Hi,

The process combines nitrogen from the air with hydrogen derived mainly from natural gas (methane) into ammonia. The reaction is reversible and the production of ammonia is exothermic.

This process is used in the manufacturing of ammonia 

Reaction -->

N₂ + 3H₂ --> 2NH₃

Ratio of Nitrogen and hydrogen by volume taken as 1:3 in the presence of Iron(catalyst) at 400-500⁰C

Thanks for asking

Good day :)