One mole of nitrogen gas combines with three moles of gaseous hydrogen to create two moles of gaseous ammonia according to the following equation:

 

N_2(g) + 3_2(g) 2NH_3(g)

 

This reaction is commercially important in the production of fertilizer. By adjusting the pressure and temperature, the reaction can be pushed forward, favoring the production of ammonia. Since German chemist Fritz Haber was instrumental in formulating a method for synthesizing ammonia, the reaction is closely associated with his name.