Question

The flow chart below shows the large scale manufacture of ammonia gas and some ammonium compounds. Study it and answer the questions that follow.

1. What are the sources of the following raw materials?
   • Hydrogen gas. 
   • Nitrogen gas.
2. What optimum conditions are needed during the manufacture of ammonia in the
   • Compressor. 
   • Catalytic chamber. 
3. Why should the gas be passed through the compressor. 
4. Write an equation for the reaction that occurs in Step 1.
5. Write the formula of the compound B. 
6. Calculate the percentage of nitrogen in compound A. 
7. What observation would be made if compound C was added to a sample suspected to contain copper (II) ions dropwise then in excess?

Answer 1

1. What are the sources of the following raw materials?
   • Hydrogen gas. 
     • Natural gas – e.g. Methane
     • Crude oil
     • Electrolysis of acidified water or brine
   • Nitrogen gas. - Fractional distillation of liquid air.
2. What optimum conditions are needed during the manufacture of ammonia in the
   • Compressor.  - Pressure of 200 – 500 atm.
   • Catalytic chamber. - Temperature of 400 - 500°C.
                                                 Finely divided iron.
3. Why should the gas be passed through the compressor. (1 mark)
   • To compress the gases to high pressure which favour high yield of ammonia.
4. Write an equation for the reaction that occurs in Step 1. (1 mark)
   • 2NH_3(g) + H₂SO_4(aq)  (NH₄)2SO_4(aq)
5. Write the formula of the compound B. (1 mark)
   • NH₄NO₃
6. Calculate the percentage of nitrogen in compound A. (2 marks)
   • (NH₄)2SO₄ = 132
     % of N
7. What observation would be made if compound C was added to a sample suspected to contain copper (II) ions dropwise then in excess?
   • A pale blue precipitate on addition of a few drops precipitate dissolves in excess of C to form a deep blue solution.