The Haber Process (AQA GCSE Chemistry)
Revision Note
The Haber process
Ammonia is manufactured using the Haber Process which occurs in five stages
The reactants are hydrogen and nitrogen which are extracted from methane and the air respectively
Stage 1: H2 and N2 gases are pumped into the compressor through pipes
Stage 2: The gases are compressed to about 200 atmospheres inside the compressor
Stage 3: The pressurised gases are pumped into a tank containing layers of catalytic iron beads at a temperature of 450°C. Some of the hydrogen and nitrogen react to form ammonia in the following reversible reaction:
N2 (g) + 3H2 (g) ⇌ 2NH3 (g)
Stage 4: Unreacted H2 and N2 and product ammonia pass into a cooling tank. The ammonia is liquefied and removed to pressurised storage vessels
Stage 5: The unreacted H2 and N2 gases are recycled back into the system
The production of ammonia by the Haber Process
Worked Example
Ammonia is produced during the Haber Process. The reaction is summarised in the diagram below.
a) Give the name of gas A.
b) Name the catalyst B used and state why it is used
Answer
a) Hydrogen
b) Iron. Speeds up the reaction/ increases the rate of reaction
Examiner Tips and Tricks
The air contains 78% nitrogen and it is removed by fractional distillation. Hydrogen is derived from methane (CH4) in a process called steam reforming.
You've read 0 of your 5 free revision notes this week
Sign up now. It’s free!
Did this page help you?