# A student is studying the production of methanol, which is manufactured industrially using the reversible reaction: CO(g) + 2H₂(g) ⇌ CH₃OH(g). The forward reaction is exothermic. The industrial process uses a copper-based catalyst and operates at a temperature of around 250 °C and a pressure of around 50–100 atmospheres. Explain how using a catalyst and a high pressure each affect the rate of reaction and the position of equilibrium in this process.

> OCR A-Level Chemistry A (H432) — 5.3 Transition elements · Explain · 5 marks

> Methanol is an important industrial chemical used as a fuel and as a starting material for making other chemicals. It is produced from carbon monoxide and hydrogen gases in the presence of a copper-based catalyst.

## Mark scheme (5 marks)

1. The catalyst increases the rate of reaction by providing a different reaction pathway with a lower activation energy.
2. The catalyst does not change / shift the position of equilibrium (it speeds up both the forward and backward reactions equally).
3. Increasing pressure means gaseous particles are closer together, so they collide more frequently, leading to a higher rate of successful collisions and a faster rate of reaction.
4. Increasing pressure shifts the equilibrium position towards the side with the smaller number of moles of gas, which is the product side (right-hand side) in this reaction.
5. Therefore, high pressure increases both the rate of reaction and the yield of methanol (more product formed at equilibrium).

## Key terms

- [catalyst](https://www.gradenine.co.uk/glossary/catalyst)
- [pressure](https://www.gradenine.co.uk/glossary/pressure)
- [position of equilibrium](https://www.gradenine.co.uk/glossary/position-of-equilibrium)

## Related

- [Revision notes for OCR A-Level Chemistry A (H432)](https://www.gradenine.co.uk/learn)
- [How to answer "Explain" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
- [Practice this with AI marking (free)](https://www.gradenine.co.uk/start)

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Source: [GradeNine](https://www.gradenine.co.uk/q/a-student-is-studying-the-production-ad8951ac) · Published by Druglandscape Ltd.