7.1.10—Conditions used in the Haber process

The Haber process makes ammonia: N₂(g)+3H₂(g)⇌2NH₃(g), an exothermic equilibrium with fewer gas moles on the product side.

High pressure favours ammonia, lower temperature favours yield but slows the reaction, and an iron catalyst increases rate without changing equilibrium position. Industry chooses a compromise condition and recycles unreacted gases.

Raising pressure improves equilibrium yield but increases equipment cost. A moderate temperature with an iron catalyst gives an economically useful throughput rather than the maximum possible yield.

The catalyst does not move equilibrium right. “Compromise temperature” means balancing rate and yield, not ignoring the exothermic nature of the reaction.