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,6.1
The Haber Process
Used to produce ammonia from nitrogen gas and hydrogen gas.
(g) (g) (g)
The nitrogen is obtained from the air.
The hydrogen is obtained from hydrocarbons(natural gas/crude oil)
In industry, ammonia is made at a pressure of 200 atm and temperature of 450°C with the
iron catalyst.
What should increase products made What the industry do
higher pressure A compromised pressure 200 atm
because it’s expensive and dangerous to
have high pressures.
lower temperature (forward reaction is A compromised temperature 450°C
exothermic) because low temperatures have lower rate
of reaction
Using iron catalyst to speed up the reaction to get to the equilibrium proportions quicker.
DOESN’T AFFECT THE POSITION OF EQUILIBRIUM
Reduce temperature needed so there is a higher % yield → reduce costs.
Unused nitrogen and hydrogen are recycled.
Ammonia is formed as a gas but it is removed after being cooled in the condenser.
(image from bbcbitesize)
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, Fertilisers
3 main elements in fertilisers – nitrogen, phosphorus, potassium
Fertilisers replace these missing elements in the soil or provide more of them.
Ammonia (base) can be neutralised by acids to make ammonium salts.
What we react What we get
nitric acid + ammonia → ammonium nitrate
Sulfuric acid + ammonia → ammonium sulfate
Phosphoric acid + ammonia → Ammonium phosphate
Nitric acid + potassium hydroxide → Potassium nitrate
Ammonia is obtained from the Haber process;
Phosphoric acid from phosphate rock;
Sulfuric acid from the Contact process;
(image from savemyexam)
Titration is used for the neutralisation of ammonia and nitric acid , ammonia and Sulfuric
acid, ammonia and phosphoric acid
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