In the Haber process, nitrogen and hydrogen gases react to form ammonia in a reversible reaction:
N2(g)+3H2(g)⇌2NH3(g) \text{N}_2(\text{g}) + 3\text{H}_2(\text{g}) \rightleftharpoons 2\text{NH}_3(\text{g}) N2(g)+3H2(g)⇌2NH3(g)An iron catalyst is used in this reaction. What is the effect of adding this catalyst?
The equilibrium yield of ammonia is increased.
The time taken to reach equilibrium is decreased.
The activation energy of only the forward reaction is decreased.
The enthalpy change of the reaction becomes more negative.
25 exam-style questions on OCR GCSE Chemistry Equilibria. Each one has a worked solution and a mark scheme showing where the marks go.