Skip to content

Course home

Equilibria

Equilibria

EasyMediumHard
1
Question 1

Methanol is manufactured industrially by reacting carbon monoxide, CO\text{CO}CO, with hydrogen, H2\text{H}_2H2​.

The reaction is reversible, exothermic, and occurs in a closed system:

CO(g)+2H2(g)⇌CH3OH(g)ΔH=−91 kJ mol−1 \text{CO(g)} + 2\text{H}_2\text{(g)} \rightleftharpoons \text{CH}_3\text{OH(g)} \quad \Delta H = -91\text{ kJ mol}^{-1} CO(g)+2H2​(g)⇌CH3​OH(g)ΔH=−91 kJ mol−1

Only 10%10\%10% of the reactants are converted into methanol at each pass through the reactor. By cooling the mixture to condense and remove the methanol as a liquid, and then recycling the unreacted gases back into the reactor, it is possible to achieve an overall 95%95\%95% conversion.

The reaction is carried out under the following conditions:

  • Temperature: 250∘C250^\circ\text{C}250∘C
  • Pressure: 50−100 atm50-100\text{ atm}50−100 atm
  • Catalyst: Copper-based catalyst (Cu/ZnO/Al2O3\text{Cu}/\text{ZnO}/\text{Al}_2\text{O}_3Cu/ZnO/Al2​O3​)

Explain why these conditions and the recycling process are chosen for methanol production, referring to reaction rates, position of equilibrium, and economic factors.

[6]
Markscheme

Equilibria Questions

  1. GCSE
  2. /Chemistry
  3. /Equilibria

25 exam-style questions on OCR GCSE Chemistry Equilibria. Each one has a worked solution and a mark scheme showing where the marks go.

Question bank