Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Chapter
Electrolysis
198 practice questions
Topics covered
- Why things conduct electricity17 practice questions
- Passing electricity through compounds: electrolysis20 practice questions
- The electrolysis of molten compounds19 practice questions
- Electrolysis and redox19 practice questions
- The electrolysis of other molten substances19 practice questions
- The electrolysis of aqueous solutions18 practice questions
- The electrolysis of sodium chloride solution19 practice questions
- The electrolysis of copper(ii) sulfate solution using inert electrodes18 practice questions
- The electrolysis of some other solutions using inert electrodes19 practice questions
- What would happen with non-electrolytes?19 practice questions
Practice questions
51–60 of 198
Question 51
4 marks · Normal
Answer and see the solution →The diagram below shows the electrolysis of molten copper(II) bromide (CuBr2) using carbon electrodes.
Apparatus for electrolysis of molten copper(II) bromide. (a)[1 mark]Identify the ions present in molten copper(II) bromide.
(b)[1 mark]State what is produced at the cathode and at the anode.
(c)[1 mark]Write the half-equation for the reaction at the cathode.
(d)[1 mark]Describe a visible change that would be observed at the anode during electrolysis.
Question 52
3 marks · Normal
Answer and see the solution →Molten sodium chloride (NaCl) is electrolysed using inert electrodes.
(a)[1 mark]State the ions present in molten sodium chloride.
(b)[1 mark]Write the balanced half-equation for the reaction at the cathode.
(c)[1 mark]Identify the product formed at the anode and write the half-equation for its formation.
Question 53
3 marks · Normal
Answer and see the solution →Electrolysis is carried out on molten magnesium chloride (MgCl2) using inert electrodes.
(a)[1 mark]Predict the product formed at the anode. Explain your answer.
(b)[1 mark]Write a balanced half-equation for the reaction at the cathode.
(c)[1 mark]Explain why molten magnesium chloride conducts electricity, but solid magnesium chloride does not.
Question 54
2 marks · Hard
Answer and see the solution →During the electrolysis of molten silver(I) chloride ( ), inert electrodes are used.
Write the half-equation for the reaction that occurs at the cathode. State whether reduction or oxidation is taking place at the cathode.
Question 55
5 marks · Hard
Answer and see the solution →Molten iron(III) bromide ( ) is electrolysed using inert electrodes.
(a)[1 mark]State the formulae of the ions present in molten .
(b)[1 mark]Identify the product formed at the cathode.
(c)[1 mark]Write the half-equation for the reaction at the cathode.
(d)[1 mark]Write the half-equation for the reaction at the anode.
(e)[1 mark]Explain why only the ions in are discharged during the electrolysis of its molten form.
Question 56
2 marks · Hard
Answer and see the solution →Write the half-equation for the reaction at the anode during the electrolysis of molten cadmium(II) iodide ( ).
Explain why this reaction is classified as oxidation.
Question 57
1 mark · Easy
Answer and see the solution →State what is meant by: reduction, in terms of electron transfer.
Question 58
3 marks · Easy
Answer and see the solution →The diagram shows the essential parts of an apparatus for the electrolysis of molten magnesium chloride (MgCl).
(a)[1 mark]What does it mean to 'discharge' a chloride ion (Cl) at the electrode?
(b)[1 mark]State what happens to the charge of a chloride ion when it is discharged.
(c)[1 mark]Describe briefly what is formed when chloride ions are discharged at the anode.
Question 59
2 marks · Easy
Answer and see the solution →During the electrolysis of molten sodium iodide (NaI), the following half-equations occur:
For each electrode, state whether the reaction is oxidation or reduction.
(a)[1 mark]Reaction at the anode:
(b)[1 mark]Reaction at the cathode:
Question 60
2 marks · Easy
Answer and see the solution →Explain how the OILRIG mnemonic helps you decide whether a process is oxidation or reduction, using the example of an ion gaining electrons.