Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Section
What are catalysts?
19 practice questions
Practice questions
1–8 of 8 · Normal
Question 1
2 marks · Normal
Answer and see the solution →State what a catalyst is and explain why the same catalyst can be used again in another reaction of the same type.
Question 2
4 marks · Normal
Answer and see the solution →(a)[2 marks]Write a word equation and a balanced symbol equation for the catalytic decomposition of hydrogen peroxide.
(b)[2 marks]Explain why manganese(IV) oxide is described as a catalyst in this reaction.
Question 3
3 marks · Normal
Answer and see the solution →Explain, with reasons, how you could show experimentally that manganese(IV) oxide is not chemically changed during the decomposition of hydrogen peroxide.
Question 4
4 marks · Normal
Answer and see the solution →The table shows the volume of oxygen gas collected over 60 seconds when hydrogen peroxide is decomposed using three different solids as potential catalysts. The experiment used the same conditions (temperature, concentration, volumes).
Oxygen collected over time Time (s) MnO2 (cm³) PbO2 (cm³) CuO (cm³) 0 0 0 0 20 24 8 0 40 36 13 0 60 40 16 0 (a)[2 marks]Compare the effectiveness of the three solids as catalysts for this reaction.
(b)[2 marks]Using evidence from the data, explain your answer.
Question 5
1 mark · Normal
Answer and check →Which statement best describes the role of a catalyst?
- A.A catalyst increases the rate of a reaction and is chemically unchanged at the end.
- B.A catalyst is used up during the reaction.
- C.A catalyst stops chemical reactions from taking place.
- D.A catalyst increases the yield of products in a reaction.
Question 6
2 marks · Normal
Answer and see the solution →Give two reasons why catalysts are important in industrial chemical processes.
Question 7
4 marks · Normal
Answer and see the solution →(a)[2 marks]Describe how you would set up an experiment to measure the effect of different solid catalysts on the rate of decomposition of hydrogen peroxide.
(b)[1 mark]State one safety precaution you would take when carrying out this experiment.
(c)[1 mark]What result would show that a solid is not a catalyst for this reaction?
Question 8
3 marks · Normal
Answer and see the solution →A chemistry student investigates the decomposition of hydrogen peroxide ( ) by measuring the volume of oxygen gas produced in 60 seconds, with and without a catalyst present. The results are:
Experiment Catalyst present? Volume of O produced/cm (in 60 s) 1 No 2.5 2 Yes 22.0 a) Calculate the average rate of oxygen production (in cm/s) for Experiment 1.
b) Calculate the average rate of oxygen production (in cm/s) for Experiment 2.
c) By how many times does the catalyst increase the rate of oxygen production compared to the experiment without a catalyst? Give your answer to 1 decimal place.
(a)[1 mark]Calculate the average rate of oxygen production for Experiment 1.
(b)[1 mark]Calculate the average rate of oxygen production for Experiment 2.
(c)[1 mark]By how many times does the catalyst increase the rate of oxygen production compared to the experiment without a catalyst? Give your answer to 1 decimal place.