Consider the reaction represented by the following equation: N2(g) + 3H2(g) ⇌ 2NH3(g); ∆H = - 92kJmol1. Finely divided iron is used as catalyst in the react...

The finely divided iron catalyst is used to shorten the time for the attainment of equilibrium in the reaction. A catalyst is a substance that increases the rate of a chemical reaction without undergoing any permanent change itself. In the Haber process, which is the industrial process for the production of ammonia, the reaction is slow at room temperature and pressure, even though the overall enthalpy change (∆H) is negative (exothermic). By adding a catalyst such as finely divided iron, the activation energy required for the reaction to proceed is lowered, which speeds up the reaction and allows the system to attain equilibrium faster. This results in a higher yield of ammonia in a shorter amount of time.