1.1. In the Haber process, nitrogen and hydrogen react to produce ammonia.

The reaction between nitrogen and hydrogen is exothermic.

Draw a reaction profile for this reaction.

1.2. The reaction between nitrogen and hydrogen in the Haber process is reversible.

The graph in Figure 2 shows how the percentage yield of the product of this reaction, ammonia, varies at different temperatures and pressures.

Figure 2 

Suggest, using Figure 2,  the conditions that would produce the greatest yield of ammonia. 

1.3. In the Haber process, the conditions used to produce ammonia are not those that would give the greatest yield.

Using Figure 2, suggest and explain why. 

1.4. Purified hydrogen and nitrogen are also passed over powdered iron in the Haber process.

Explain why.