Nitrogen combines with hydrogen to produce ammonia when an iron catalyst is present. This reaction can proceed in both directions. $\text{N}_2(g) + 3\text{H}_2(g) \rightleftharpoons 2\text{NH}_3(g)$ Which statement about this reaction is correct?
- AThe iron catalyst decreases the activation energy of only the forward reaction.
- BWhen equilibrium is reached, the forward reaction has stopped.
- CWhen the pressure changes, the concentration of ammonia at equilibrium remains constant.
- DNitrogen and hydrogen never completely convert to ammonia.