1. Making ammonia The Haber process

2. The Haber process What do we need?
Where do we get the nitrogen and hydrogen?
Nitrogen – Fractional distillation of air
Hydrogen – From natural gas, CH4 (reforming). Also electrolysis of water.

3. Why is the Haber process so important?
Plants need nitrogen to grow.
They get this from soluble nitrates (NO3-) in the soil.
When we harvest plants, the nitrogen is not returned to the soil.
Ammonia is used to make nitrate fertilisers to replenish the soil.

4. The Haber process What are the conditions?
Iron catalyst
High temperature (450oC)
High pressure (200atm)

5. The Haber process It’s reversible
There is always a mixture of nitrogen, hydrogen and ammonia.
How do we get the ammonia pure?

6. The Haber process It’s reversible
Ammonia has a higher boiling point than hydrogen and nitrogen.
The reaction mixture is cooled and the ammonia condenses.

7. The Haber process It’s reversible
The liquefied ammonia is collected.
The hydrogen and ammonia gases are recycled back into the reaction vessel.

8. Making ammonia The Haber process
200atm
Iron catalyst

9. List three conditions for the Haber process 1. 2. 3.
Ammonia is an important chemical used for making …………………… The raw materials to make it are …………………… (from the …………………) and …………………. (mainly from natural ………………….). Theses are reacted at about …………………oC and ………………….. atmospheres pressure using an ………………….. catalyst. Ammonia is removed from the reaction mixture by …………………. it. This
……………….. the ammonia gas.
List three conditions for the Haber process 1. 2. 3.
Write a word and symbol equation for the Haber process
Word bank: air, fertilisers, gas, 450, hydrogen, iron, liquefies, nitrogen, 200, cooling
Complete a flow chart of the Haber process in the boxes below
Where do the reactants for the Haber process come from?
Nitrogen –
Hydrogen –
Why is the Haber process so important?
…………………………………………………………………………………