Ammonia is manufactured in an exothermic reaction between nitrogen and hydrogen in the presence of an iron catalyst: N2(g)+3H2(g)=2NH3(g)
The nitrogen and hydrogen mixture is passed into a reaction chamber at a pressure of 200 atmospheres and a temperature of 450°C. The reaction is reversible.

a) Why is a catalyst needed?

The mixture of gases leaving the reaction chamber still contains some unreacted nitrogen and hydrogen.

b) Explain how the ammonia can be separated form this unreacted nitrogen and hydrogen.

c) What is done with the unreacted nitrogen and hydrogen once the ammonia has been removed?

Ammonia can be reaction with nitric acid to make the fertilizer ammonium nitrate NH4NO3.

d) write a balanced chemical equation for the reaction between ammonia and nitric acid.

e) Describe a chemical test you would do to show that ammonium nitrate contains ammonium ions.