A manufacturer investigates some reactions related to the production of synthetic fuels.
The table shows three possible reversible reactions that could be used. The enthalpy changes are also shown.
| Reaction | Equation | ΔH\Delta HΔH in kJ/mol |
|---|---|---|
| 1 | CO(g)+3H2(g)⇌CH4(g)+H2O(g)\text{CO}(\text{g}) + 3\text{H}_2(\text{g}) \rightleftharpoons \text{CH}_4(\text{g}) + \text{H}_2\text{O}(\text{g})CO(g)+3H2(g)⇌CH4(g)+H2O(g) | −206-206−206 |
| 2 | CO2(g)+H2(g)⇌CO(g)+H2O(g)\text{CO}_2(\text{g}) + \text{H}_2(\text{g}) \rightleftharpoons \text{CO}(\text{g}) + \text{H}_2\text{O}(\text{g})CO2(g)+H2(g)⇌CO(g)+H2O(g) | +41+41+41 |
| 3 | CO2(g)+4H2(g)⇌CH4(g)+2H2O(g)\text{CO}_2(\text{g}) + 4\text{H}_2(\text{g}) \rightleftharpoons \text{CH}_4(\text{g}) + 2\text{H}_2\text{O}(\text{g})CO2(g)+4H2(g)⇌CH4(g)+2H2O(g) | −165-165−165 |
For reaction 1, predict whether the pressure should be low or high to give the greatest yield of products.
Give a reason for your choice.
For reaction 1, predict whether the temperature should be low or high to give the greatest yield of products.
Give a reason for your choice.
For reaction 2, suggest why changing the temperature will have less effect on the yield of products than in reactions 1 and 3.
For reaction 3, predict the effect on the rate of the forward reaction of increasing the pressure, without changing the temperature.
Explain your prediction in terms of the particle collision theory.
The manufacturer makes a batch of ethyl ethanoate from ethanol and ethanoic acid using this reaction:
C2H5OH+CH3COOH→CH3COOC2H5+H2O \text{C}_2\text{H}_5\text{OH} + \text{CH}_3\text{COOH} \rightarrow \text{CH}_3\text{COOC}_2\text{H}_5 + \text{H}_2\text{O} C2H5OH+CH3COOH→CH3COOC2H5+H2OHe starts with 92 kg92 \text{ kg}92 kg of ethanol. Calculate the maximum mass of ethyl ethanoate he could obtain.
28 exam-style questions on Edexcel IGCSE Chemistry Reversible reactions and equilibria. Each one has a worked solution and a mark scheme showing where the marks go.