14: Making fertilisers

Question 1

Examples of nitrogenous fertilisers manufactured from ammonia

Answer 1

urea (NH2)2CO
ammonium nitrate NH4NO3
ammonium sulfate (NH4)2SO4
ammonium phosphate (NH4)3PO4

Question 2

Other nitrogenous fertilisers not manufactured from ammonia

Answer 2

Potassium nitrate KNO3

Question 3

Ammonium salts as a product of ammonia when it neutralises acids

Answer 3

Ammonium nitrate with nitric acid
Ammonium sulfate with sulphuric acid
Ammonium phosphate with phosphoric acid

Question 4

Steps to making a fertiliser from an acid and alkali in a lab

Answer 4

1. Add alkali to a flask. Add a few drops of indicator. Add acid from the burette until indicator changes colour. Not volume of acid needed
2. Repeat step 1 but without indicator using noted volume of acid
3. Heat salt solution made in step 2 to reduce volume. Leave it to cool so that crystals form
4. Filter the mixture to separate crystals. leave to dry