Starch is broken down in the body during digestion.
What type of substance acts as a catalyst in this process?
In industry, methanol (CH3OH\text{CH}_3\text{OH}CH3OH) is produced by reacting carbon monoxide with hydrogen.
The equation for the reaction is:
CO(g)+2H2(g)⇌CH3OH(g) \text{CO}(\text{g}) + 2\text{H}_2(\text{g}) \rightleftharpoons \text{CH}_3\text{OH}(\text{g}) CO(g)+2H2(g)⇌CH3OH(g)How many moles of hydrogen react completely with 1.8×1051.8 \times 10^51.8×105 moles of carbon monoxide?
The reaction is carried out at a temperature of 250 ∘C250\ ^\circ\text{C}250 ∘C and a pressure of 100100100 atmospheres.
The forward reaction is exothermic.
Explain what happens to the equilibrium yield of methanol if a temperature higher than 250 ∘C250\ ^\circ\text{C}250 ∘C is used.
A pressure of 100100100 atmospheres is used instead of atmospheric pressure.
The higher pressure gives a greater yield of methanol and an increased rate of reaction.
Explain why.
A copper-based catalyst is used in the reaction to produce methanol.
Explain how a catalyst increases the rate of a chemical reaction.
Suggest why a catalyst is used in this industrial process.
Do not give answers in terms of increasing the rate of reaction.
Determine the effect of using the catalyst on the equilibrium yield of methanol.
21 exam-style questions on AQA GCSE Chemistry 6.2 Reversible reactions and dynamic equilibrium, covering 6.2.1 Reversible reactions, 6.2.2 Energy changes and reversible reactions, 6.2.3 Equilibrium, 6.2.4 The effect of changing conditions on equilibrium (HT only), 6.2.5 The effect of changing concentration (HT only), 6.2.6 The effect of temperature changes on equilibrium (HT only), and 6.2.7 The effect of pressure changes on equilibrium (HT only). Each one has a worked solution and a mark scheme showing where the marks go.