Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Chapter
Rates of Reaction
164 practice questions
Topics covered
- Experiments to measure the rate of reaction19 practice questions
- Explaining what's happening19 practice questions
- Changing the surface area of the reactants19 practice questions
- Changing the concentration of the reactants19 practice questions
- Changing the pressure on the reaction19 practice questions
- What are catalysts?19 practice questions
- How does a catalyst work?20 practice questions
- Catalysts in industry19 practice questions
Practice questions
41–50 of 164
Question 41
2 marks · Easy
Answer and see the solution →Two pieces of magnesium ribbon, A and B, have the same mass. Ribbon B is cut into 4 equal shorter pieces. Both are added to separate beakers with the same volume and concentration of hydrochloric acid at the same temperature.
Ribbon A takes 200 seconds to finish reacting. Estimate how the time taken for Ribbon B to finish reacting compares to A, and explain your reasoning.
Question 42
2 marks · Easy
Answer and see the solution →Explain why a reaction between a solid and a liquid is faster when the solid is ground into a fine powder rather than used as one large lump.
Question 43
3 marks · Easy
Answer and see the solution →The graph below shows how the mass of carbon dioxide produced changes over time during the reaction between excess hydrochloric acid and two forms of calcium carbonate, both of the same mass.
Graph: Mass of CO2 produced (g) vs. Time (minutes) (a)[1 mark]Which form of calcium carbonate reacts faster? Give evidence from the graph.
(b)[1 mark]State the total mass of carbon dioxide produced at the end of both reactions.
(c)[1 mark]Explain why both forms produce the same final mass of carbon dioxide.
Question 44
1 mark · Easy
Answer and see the solution →Complete the sentence: Reactions between a solid and a liquid are faster when the solid has a ________ surface area.
Question 45
3 marks · Easy
Answer and see the solution →Iron filings (very small pieces) and an iron nail (large piece) are both placed separately into dilute sulfuric acid. The mass of each iron sample is the same.
(a)[1 mark]State which form of iron will react more quickly.
(b)[2 marks]Describe two reasons why the form you selected in (a) reacts faster.
Question 46
2 marks · Easy
Answer and see the solution →A reaction between a solid and a liquid produced 32 cm³ of gas in 4 minutes. When the same mass of solid is powdered and reacted in the same conditions, the reaction is complete in 2 minutes. Calculate the average rate of gas production in both cases. Give your answers in cm³/min and compare the results.
Question 47
2 marks · Normal
Answer and see the solution →A student reacts powdered calcium carbonate with dilute hydrochloric acid. Explain why the reaction happens faster than if the same mass of calcium carbonate is in large lumps, not powder.
Question 48
4 marks · Normal
Answer and see the solution →Solid magnesium ribbon reacts with dilute sulfuric acid to produce hydrogen gas. A student wants to investigate how changing the surface area of magnesium affects the rate of reaction.
(a)[1 mark]Describe a change the student could make to increase the surface area of magnesium used.
(b)[2 marks]Explain how this change affects the rate of the reaction.
(c)[1 mark]State one variable other than surface area that should be kept constant in this investigation.
Question 49
3 marks · Normal
Answer and see the solution →A student conducts two experiments: - Experiment 1: 5.0 g of marble chips (large lumps) - Experiment 2: 5.0 g marble powder Both react with identical volumes and concentrations of dilute hydrochloric acid at the same temperature. In Experiment 1, all the marble has reacted in 7 minutes. In Experiment 2, the reaction is complete in 2 minutes.
Calculate the average rate of reaction in grams of marble reacted per minute for: (a) Experiment 1 (b) Experiment 2.
Question 50
3 marks · Normal
Answer and see the solution →A factory grinds solid reactants used in a chemical process into fine powder instead of using large lumps. Explain, with reasons, how and why this affects the rate of the reaction.