In the Haber process, nitrogen and hydrogen react to form ammonia.The balanced equation corresponding to the above reaction is given as:
N2 + 3H2 ↔ 2NH3
Based on the reaction stoichiometry:
1 mole of N2 combines with 3 moles of H2 to form 2 moles of ammonia
In terms of reaction rates; the rate of consumption of reactants and that of the formation of products is given as:
-d[N2]/dt = -1/3 *d[H2]/dt = 1/2* d[NH3]/dt
Negative sign indicates that the concentration of reactants decreases with time. With respect to H2 and NH3 the relationship is given as:
d[NH3]/dt = 2/3 * d[H2]/dt