Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Section
The electrolysis of aqueous solutions
18 practice questions
Practice questions
1–7 of 7 · Easy
Question 1
1 mark · Easy
Answer and see the solution →State why the volume of chlorine gas collected at the anode is usually less than expected during the electrolysis of concentrated sodium chloride solution.
Question 2
3 marks · Easy
Answer and see the solution →A student is asked to investigate the electrolysis of an aqueous sodium chloride solution in the laboratory.
(a)[2 marks]Describe how you would set up apparatus to collect the products formed during this electrolysis.
(b)[1 mark]State one safety precaution you should take when performing this experiment.
Question 3
2 marks · Easy
Answer and see the solution →During the electrolysis of concentrated sodium chloride solution, a total of 8 cm³ of gas is collected at the cathode. The experiment is carried out at room temperature and pressure.
(a)[1 mark]Name the product formed at the cathode.
(b)[1 mark]What volume of chlorine gas would you expect to collect at the anode under the same conditions?
Question 4
2 marks · Easy
Answer and see the solution →A student finds that the volume of chlorine gas collected during the electrolysis of concentrated sodium chloride solution is less than expected.
(a)[1 mark]Explain why less chlorine gas is collected than expected.
(b)[1 mark]Suggest one way you could change the experiment to collect more chlorine gas.
Question 5
1 mark · Easy
Answer and see the solution →Name one piece of apparatus you would need to collect the gas produced at the cathode during the electrolysis of concentrated sodium chloride solution.
Question 6
3 marks · Easy
Answer and see the solution →The electrolysis of concentrated sodium chloride solution is carried out using carbon electrodes.
(a)[1 mark]State the product formed at the cathode.
(b)[1 mark]State the product formed at the anode.
(c)[1 mark]Write a word equation for the reaction that occurs at the anode.
Question 7
2 marks · Easy
Answer and see the solution →In an experiment, 12 cm³ of hydrogen gas is collected at the cathode during the electrolysis of concentrated sodium chloride solution. The theoretical volume of chlorine expected at the anode is also 12 cm³, but only 7 cm³ is collected.
Calculate the difference between the expected and the actual volume of chlorine collected. Explain why there is this difference.