Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Section
Changing the surface area of the reactants
19 practice questions
Practice questions
1–8 of 8 · Easy
Question 1
1 mark · Easy
Answer and see the solution →State what happens to the rate of reaction when a solid reactant is broken into smaller pieces, keeping all other conditions the same.
Question 2
3 marks · Easy
Answer and see the solution →A student compares the reaction between calcium carbonate and hydrochloric acid using two forms of calcium carbonate: large lumps and powdered. All other conditions are kept the same.
(a)[1 mark]State which form will react faster.
(b)[2 marks]Explain why this form reacts faster.
Question 3
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 4
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 5
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 6
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 7
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 8
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.