Year 12 Chemistry Tutorial 9.4.B.2 – Haber Process Module 9.4 – Chemical Monitoring and Management Topic 9.4.B – Haber Process Name 1.
Date Using an iron catalyst, chemists can synthesise ammonia, NH3, from its component elements. Write an equation for this reaction. …………………………………………………………………………………………………………………………………………………………………………………………. 2.
Once synthesised, ammonia can be oxidised to nitric acid and other useful chemicals such as plastics, fertilisers, medicines and explosives. Give one other household use for ammonia. …………………………………………………………………………………………………………………………………………………………………………………………. 3.
Fritz Haber was the first to develop this process and Carl Bosch modified the process to suit industry in 1913. They obtained nitrogen gas from liquefied air and hydrogen gas from decomposing steam over hot coal. (a) Name the separation technique that could be used to obtain nitrogen. …………………………………………………………………………………………………………………………………………………………………………………… (b) Give the equation for the decomposition reaction that that produces hydrogen. …………………………………………………………………………………………………………………………………………………………………………………… (c) Explain why high temperatures increase the rate of this reaction. …………………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………………… 4.
High temperatures decrease the yield of ammonia. (a) Define ‘yield’. …………………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………………… (b) Use the information above to determine whether the forward reaction is exothermic or endothermic. Explain using Le Chatelier’s principle. …………………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………………… 5.
6.
Using an iron oxide catalyst and a moderate temperature of about 500˚C solves the problem of running the reaction at a lower temperature. What is the function of the catalyst? …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. ………………………………………………………………………………………………………………………………………………………………………………………… Explain why the Haber process is a delicate balancing act involving reaction rate and equilibrium. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. 7.
Explain why high pressure also increases the rate of this reaction. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. Page 2 8.
9.
High pressure also increases the yield of ammonia. Explain, using Le Chatelier’s principle, why a relatively high pressure of 250 atm is used. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. As ammonia is formed, it is liquefied and removed. Explain how this increases the yield of ammonia. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. 10. Chemists involved in the Haber Process need to continually monitor the reaction chamber. Give THREE conditions that need careful monitoring and explain why. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. Page 3 11. Analyse and describe the data in the graph below. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. th
12. Why was there a world-­‐wide demand for ammonia in the early 20 Century? …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. 13. From what source and place did the world get its ammonia at that time? …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. 14. The exploitation of ammonia had the ability to both sustain and destroy life. What was Haber’s inspiration for his research? …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. Page 4 15. Haber’s contributions helped sustain the German war effort during World War I. What were his major contributions to his country during the war? …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. 16. Why did Haber eventually leave Germany? …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. 17. How would you describe the conditions under which Haber developed the industrial synthesis of ammonia? …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. Page 5 18. Evaluate the significance of these conditions at that time in world history. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………………………………………………………………………………. Page 6