Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Unit
Physical Chemistry
442 practice questions
Topics covered
Practice questions
91–100 of 183 · Easy
Question 91
2 marks · Easy
Answer and see the solution →A student compresses a liquid to try to double the rate of reaction. The initial time taken for the reaction is 30 minutes. Calculate the likely time taken to complete the reaction after the pressure is doubled. Explain your answer.
Question 92
1 mark · Easy
Answer and see the solution →State what a catalyst does in a chemical reaction.
Question 93
3 marks · Easy
Answer and see the solution →(a)[1 mark]Describe what happens to a catalyst at the end of a chemical reaction.
(b)[1 mark]Explain why only a small amount of catalyst is needed to speed up a reaction.
(c)[1 mark]Different reactions require different catalysts. Give one reason for this.
Question 94
2 marks · Easy
Answer and see the solution →Explain why a catalyst is not included in the balanced chemical equation for a reaction, even though it is present and important during the reaction.
Question 95
3 marks · Easy
Answer and see the solution →(a)[1 mark]Oxygen collected (cm³) from decomposition of hydrogen peroxide over 60 seconds using solid W, X, or Y as a catalyst. Solid Oxygen Produced (cm³) W 24 X 2 Y 0 Which solid appears to be the most effective catalyst for this reaction?
(b)[1 mark]Suggest which solid does not act as a catalyst in this reaction.
(c)[1 mark]Give a reason for your answer to part (b).
Question 96
1 mark · Easy
Answer and see the solution →Name the biological catalyst found in potatoes that speeds up the decomposition of hydrogen peroxide.
Question 97
3 marks · Easy
Answer and see the solution →(a)[1 mark]Write the word equation for the decomposition of hydrogen peroxide.
(b)[1 mark]Write the balanced symbol equation for this reaction.
(c)[1 mark]Explain why the catalyst is not shown among the reactants or products in these equations.
Question 98
2 marks · Easy
Answer and see the solution →If 0.20 g of manganese(IV) oxide is used to catalyse four separate 100 cm³ portions of hydrogen peroxide, how much manganese(IV) oxide will remain after all four reactions are completed?
Question 99
2 marks · Easy
Answer and see the solution →A student uses 0.10 g of a catalyst in a reaction and finds that at the end of the reaction the mass of the catalyst is still 0.10 g. The student repeats the experiment with another sample of the same catalyst, starting with 0.12 g, and measures the mass again after the reaction. Explain, using a calculation, what mass of the catalyst the student should expect to find at the end of the second experiment.
Question 100
1 mark · Easy
Answer and see the solution →State what a catalyst does to the activation energy, as shown on a reaction profile diagram.