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
21–30 of 69 · Normal
Question 21
4 marks · Normal
Answer and see the solution →The table shows the total volume of gas produced over time when excess hydrochloric acid reacts separately with two forms of zinc of the same mass: powder and large granules.
Volume of gas produced (cm³) Time (min) Zinc powder (cm³) Zinc granules (cm³) 0 0 0 1 38 15 2 65 25 3 85 32 4 90 39 5 90 43 6 90 44 (a)[1 mark]Describe the difference in the rate of reaction between the powder and granules during the first 3 minutes.
(b)[1 mark]Give the total volume of gas produced at the end of both reactions.
(c)[1 mark]Explain why both forms of zinc produced the same final volume of gas.
(d)[1 mark]Explain why the reaction with zinc powder is faster.
Question 22
1 mark · Normal
Answer and check →Which change will increase the rate of a reaction between a solid and a liquid most effectively?
- A.Grinding the solid into a powder.
- B.Decreasing the temperature.
- C.Using less of the liquid.
- D.Stirring less frequently.
Question 23
2 marks · Normal
Answer and see the solution →State two factors, other than surface area, that can increase the rate of a reaction between a solid and a liquid.
Question 24
4 marks · Normal
Answer and see the solution →A teacher demonstrates the reaction between 3.0 g of magnesium powder and excess dilute hydrochloric acid in a conical flask. She prepares a second flask with 3.0 g of magnesium ribbon. Both are started at the same time.
(a)[2 marks]Predict which flask will finish producing gas first, and explain your answer.
(b)[2 marks]State the total mass of hydrogen gas produced in each flask. (Give your answer to 2 significant figures.) [M_r(H_2) = 2.0. Ar(Mg) = 24.0] Equation:
Question 25
2 marks · Normal
Answer and see the solution →Describe what happens to the rate of a chemical reaction when the concentration of one of the reactants is increased. Explain your answer.
Question 26
4 marks · Normal
Answer and see the solution →A student is given a bottle of 2.00 mol/dm³ hydrochloric acid. She prepares diluted solutions for a reaction experiment. The total final volume of each solution will be 25.0 cm³.
(a)[2 marks]Calculate the concentration (in mol/dm³) if she mixes 8.0 cm³ of the original acid with 17.0 cm³ of distilled water.
(b)[2 marks]Calculate the concentration (in mol/dm³) if she instead uses 20.0 cm³ of the original acid and 5.0 cm³ of water, making the total volume up to 25.0 cm³.
Question 27
3 marks · Normal
Answer and see the solution →In an experiment, a student finds that 0.21 g of carbon dioxide are released in the first 30 seconds of a reaction between marble chips and hydrochloric acid. Calculate the average rate of reaction (in g/s) during this time. Show your working.
Question 28
3 marks · Normal
Answer and see the solution →Explain how you can tell from a graph whether the rate of reaction is directly proportional to the concentration of the reactant.
Question 29
4 marks · Normal
Answer and see the solution →The table below gives the concentration of a reactant and the corresponding average rate of reaction measured at the start of an experiment.
Concentration of reactant and average rate Concentration of HCl (mol/dm³) Average rate (g/s) 0.50 0.004 1.00 0.008 1.50 0.012 2.00 0.016 (a)[1 mark]Describe the pattern shown by the data.
(b)[1 mark]Predict the average rate if the concentration is increased to 2.50 mol/dm³.
(c)[2 marks]Explain your answer to part b.
Question 30
1 mark · Normal
Answer and check →Which of the following is the concentration (in mol/dm³) of a solution made by mixing 6.0 cm³ of 2.00 mol/dm³ hydrochloric acid with 19.0 cm³ of distilled water to make a total of 25.0 cm³?
- A.0.30 mol/dm³
- B.0.40 mol/dm³
- C.0.48 mol/dm³
- D.0.60 mol/dm³