The Haber process
The Haber process is about the production of ammonia (NH3) – the reversible reaction is:
N2 + 3H2 <- -> 2NH3 + (heat)
Volume will be higher on the left as there is two sets of molecules (volume includes space between them) – also the reaction is exothermic towards the direction of ammonia
Industrially you need 200 atmospheres of pressure and 450 degrees C of temperature and an iron catalyst
- The high pressure favours the forward reaction – the pressure encourages the ammonia to stay together and makes it harder for them to separate back Nitrogen and hydrogen because of the pressure on them
- If the pressure was higher then you could get even more yield – but it becomes very expensive to make the pressure higher
- The forward reaction is exothermic – but you need the higher temperature to get the reaction going fast enough – (higher temperature increases the rate of reaction) – however decreases the yield of ammonia because the reaction in exothermic
Ammonia is used in creating fertiliser
The iron catalyst helps speed up the catalyst – thus allowing us to keep the temperature slightly lower but doesn’t affect the yield