AQA GCSE Chemistry Paper 2 2025 – 400 Free Practice Questions to Pass the Exam

The process of producing ammonia is commonly described by the Haber process, which involves the reaction of nitrogen and hydrogen gases. To maximize the yield of ammonia, various conditions need to be optimized based on Le Chatelier's principle and the nature of the reaction.

The formation of ammonia is an exothermic reaction, meaning that it releases heat. Consequently, lower temperatures favor the production of ammonia, as the reaction shifts to the right to produce more product in response to the removal of heat. However, if the temperature is too low, the rate of reaction becomes slow, making it impractical for production.

On the other hand, for pressure, the formation of ammonia involves a decrease in the number of gas molecules: nitrogen (N₂) and hydrogen (H₂) combine to form ammonia (NH₃). Since there are four molecules of reactants (one nitrogen and three hydrogen) for every two molecules of ammonia produced, increasing the pressure will favor the side with fewer gas molecules, which in this case is the ammonia side.

Combining these principles, low temperatures help favor the reaction's position towards ammonia, while high pressures effectively shift the equilibrium towards ammonia production. Thus, choosing a condition that maintains low temperature and high pressure would most effectively