Ammonia is made in the Haber process. The forward reaction is exothermic.
N2(g)+3H2(g)⇌2NH3(g) \mathrm{N_{2}(g) + 3H_{2}(g) \rightleftharpoons 2NH_{3}(g)} N2(g)+3H2(g)⇌2NH3(g)A temperature of about 450 ∘C450\,^\circ\mathrm{C}450∘C is used.
Why is a lower temperature not used?
A lower temperature would give a higher yield of ammonia, but the rate would be too slow.
A lower temperature would give a lower yield of ammonia, and the rate would be too slow.
A lower temperature would give a higher yield of ammonia, and the rate would be faster.
A lower temperature would give a lower yield of ammonia, but the rate would be faster.
136 exam-style questions on OCR GCSE Chemistry 6.1 Improving processes and products, covering 6.1.1 Extracting metals industrially and by electrolysis, 6.1.2 Life cycle assessment and recycling, 6.1.3 Biological methods of metal extraction, 6.1.4 The Haber process and the production of fertilisers, 6.1.5 Alloys and their uses, 6.1.6 Corrosion and its prevention, 6.1.7 Comparing and selecting materials, and 6.1.8 Industrial conditions, rate and position of equilibrium. Each one has a worked solution and a mark scheme showing where the marks go.