1. kathryn thumath
02/08/2019
KTHUMATH

2. The Haber Process This is the Industrial Manufacture of Ammonia NH3
It is made by reacting nitrogen and Hydrogen together.
Hydrogen comes from Methane or Naphtha
Nitrogen comes from the Air
The process is reversible, we will not get 100% yield.
The conditions used help increase yield Using an Iron catalyst, T = 500/600C, 175x atmospheric pressure.
02/08/2019
KTHUMATH

3. The reaction N2 + 3 H2 = 2 NH3 Making Ammonia in the Laboratory
This can be done by heating an ammonium compound with an alkali.
Example –
Ca(OH)2 + NH4Cl= CaCl2 +NH3+H2O
02/08/2019
KTHUMATH

4. Properties of Ammonia It is alkaline It is less dense than air.
It is very soluble in water
It can neutralise acids
It is a colourless gas
It has a strong “fishy” smell
It is used to make fertilisers (Ammonium salts)
It is used to make Nitric Acid
02/08/2019
KTHUMATH

5. Making Ammonium Salts
They can be made in neutralisation reactions with acids.
The experiment should be carried out using titration apparatus.
Acid fills the burette, ammonia is pipetted into a flask and a few drops of indicator is added.
The end point is when the indicator turns green.
Repeat the titration to get duplicate results and take an average.Evaporate water to get solid salt.
02/08/2019
KTHUMATH

6. Nitrogen Dioxide
NO2 can be made by sparking air. It is a brown gas. The electric spark provides the energy to break the N2 triple bond.This is not economoly viable.
It is formed when Nitrogen and Oxygen react.( It is also produced in car exhausts)
It is an acidic gas and contributes partly to acid rain.It is soluble in water- Nitric Acid
It is used to form Nitric Acid which is used to make fertilisers.
02/08/2019
KTHUMATH

7. The Ostwald Process This is the industrial manufacture of Nitric Acid.
1. Air + Ammonia = Nitrogen monoxide ( Platinum/Rhodium catalyst, 900C.
2. NO passes through cooler where it reacts with O2 forming NO2
3. NO2 and O2 pass to absorption tower, passing over water soaked glass beads.
4. The Nitric Acid produced collects at bottom of tower.
02/08/2019
KTHUMATH

8. The Equations! NH3 + Air = NO NO + Air = NO2
NO2 + H2O + O2 ( Air) = HNO3
The Nitric Acid will then be used in Neutralisation reactions to form salts - Fertilisers
02/08/2019
KTHUMATH

9. Nitrogen cycle Nitrogen In Air can be fixed in 2 ways.
Lightning storms or in root nodules.
It is used to make nitrates which are essential to make plant proteins.
Plants can be eaten by animals which covert to animal proteins. When plants or animals die the proteins are converted into ammonium compounds. Their waste manure/sewage can also be added to soil.
The ammonia is then turned back into nitrates which can be re used.
Ammonia is also made in the Haber process and can be added to the soil in compounds.
02/08/2019
KTHUMATH