Free Haber's Process MCQs with Answers
2 Haber's Process MCQs from Chemistry, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
2 questions
1. In the Haber process for manufacturing ammonia, the catalyst used is
- A. finely divided iron with promoters
- B. platinum
- C. vanadium pentoxide
- D. nickel
Explanation: Iron with small amounts of potassium and aluminium oxide as promoters is used because it is effective and cheap enough for a process operating on this scale. Vanadium pentoxide is the catalyst of the Contact process for sulphuric acid and nickel is used in the hydrogenation of oils, both of which appear here as familiar but wrong answers. The gases are recycled repeatedly since a single pass converts only about fifteen per cent.
Correct answer: finely divided iron with promoters2. The conditions actually used in the Haber process are about
- A. 1000 degrees Celsius and 1 atmosphere
- B. 25 degrees Celsius and 1000 atmospheres
- C. 450 degrees Celsius and 200 atmospheres
- D. 450 degrees Celsius and 1 atmosphere
Explanation: A moderately high temperature is a compromise, since a low temperature would give a better yield but far too slowly for industry, while high pressure genuinely improves the yield and is limited only by the cost and strength of the plant. Ammonia is removed by liquefaction and the unreacted gases are recycled, so the overall conversion is high even though each pass is poor.
Correct answer: 450 degrees Celsius and 200 atmospheres