Haber Process

Question 1

Why do we make ammonia (NH3)

Answer 1

• plants need nitrogen to synthesise amino acids
• amino acids make protein needed for growth
• makes nitrogen based fertilisers for farming

Question 2

How to make ammonia

Answer 2

• use nitrogen and hydrogen as the reactants
• get nitrogen from air
• fractional distillation of the air
• cool air down to -196
  = nitrogen turns to liquid

Question 3

Haber process equation

Answer 3

3H2 + N2 forwards 2NH3

Question 4

What is the point of the Haber process

Answer 4

To manufacture ammonia
= produces nitrogen fertilisers

Question 5

Describe the Haber process

Answer 5

• purified gases passed over a catalyst of iron at a high temp

Question 6

Source of the raw materials

Answer 6

Nitrogen- from the air
Hydrogen- reacting methane with steam

Question 7

Detailed process

Answer 7

Nitrogen and hydrogen mix into reaction vessel at 450C and 200 atmospheric pressure
Gases pass over iron catalyst
= cause some nitrogen and hydrogen to react and form ammonia
As it’s reversible mixture still contains hydrogen and nitrogen
Ammonia has low boiling point
= pass into condenser to cool ammonia into liquid ammonia whereas hydrogen and nitrogen stay as gas and are recycled

Question 8

Result of it being a reversible reaction

Answer 8

Some ammonia breaks back down into nitrogen and hydrogen

Question 9

How do we increase the yield

Answer 9

Cool the ammonia to turn it into a liquid which is removed
= then recycle unreacted nitrogen and hydrogen back over the catalyst

Question 10

Describe Le Chateliers principle

Answer 10

If a system is at equilibrium and a change is made to any of the conditions
= the system responds to counteract the change

Question 11

Things limiting high pressure

Answer 11

Expsensive
Dangerous