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
111–120 of 164
Question 111
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.
Question 112
2 marks · Hard
Answer and see the solution →State two features that are always true for catalysts when used in a chemical reaction.
Question 113
5 marks · Hard
Answer and see the solution →A student investigates the reaction below:
(a)[2 marks]Describe how the student could show that manganese(IV) oxide acts as a catalyst in this reaction.
(b)[2 marks]After the reaction, the student filters, dries, and reweighs the manganese(IV) oxide. The mass is unchanged. Explain why this result supports the conclusion that manganese(IV) oxide is a catalyst.
(c)[1 mark]State why only a small amount of catalyst is usually needed for a reaction.
Question 114
2 marks · Hard
Answer and see the solution →Explain why the same catalyst cannot usually be used for every type of chemical reaction.
Question 115
1 mark · Easy
Answer and see the solution →State what a catalyst does to the activation energy, as shown on a reaction profile diagram.
Question 116
3 marks · Easy
Answer and see the solution →(a)[1 mark]Describe the energy change from reactants to products in an exothermic reaction profile diagram.
(b)[1 mark]On a reaction profile diagram, where is the activation energy shown?
(c)[1 mark]Explain how adding a catalyst would change the appearance of the reaction profile diagram.
Question 117
2 marks · Easy
Answer and see the solution →A certain reaction without a catalyst has an activation energy of 150 kJ/mol. When a catalyst is used, the alternative pathway requires only 80 kJ/mol. Calculate the reduction in activation energy provided by the catalyst.
Question 118
2 marks · Easy
Answer and see the solution →Explain why not all particles react, even with a catalyst, and how this is shown in a reaction profile diagram.
Question 119
3 marks · Easy
Answer and see the solution →(a)[1 mark]Values for a reaction profile. Description Energy (kJ/mol) Reactants 120 Peak without catalyst 200 Peak with catalyst 140 Products 60 Calculate the activation energy without a catalyst.
(b)[1 mark]What is the activation energy with a catalyst?
(c)[1 mark]Describe how the catalyst affects the reaction profile diagram, using the values from the table.
Question 120
1 mark · Easy
Answer and see the solution →On a reaction profile diagram, what does the vertical distance between the reactants and the peak of the curve represent?