Dihydrogen nitrogen fixation

While the latter reactions are no longer used for nitrogen fixation, the reaction of dinitrogen with dihydrogen to form ammonia is among the most important industrial processes. The alkaline-earth metals react readily with dinitrogen at elevated temperatures to form nitrides lithium reacts even at room temperature with dinitrogen. 

The idealised stoichiometry for nitrogen fixation is shown in Equation (9). However, this is never attained in practice. In the absence of a substrate the enzyme reduces protons to dihydrogen according to the stoichiometry shown in Equation (10). 

---