Which row correctly identifies the cathode and the type of ion attracted to it during electrolysis?
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Practise IGCSE 0620 questions in the style of recent Extended past papers, organised by syllabus subtopic. Each set comes with an examiner-style mark scheme and a downloadable worksheet.
Everything students ask about Cambridge IGCSE 0620 Electrolysis Topical Past Papers.
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These Electrolysis Topical Past Paper Questions are written in the style of recent Cambridge IGCSE Chemistry 0620 Extended papers and grouped by the Electrochemistry (C4.1) section of the 2025–2027 syllabus. Use them to revise the exact skills examiners test in this part of the course.
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Define electrolysis. Identify products at the cathode and anode when molten/aqueous compounds are electrolysed. Apply the electrolysis of concentrated and dilute aqueous solutions (e.g. NaCl, copper(II) sulfate with inert and copper electrodes). Extended candidates explain electrolysis using ionic half-equations.
Which row correctly identifies the cathode and the type of ion attracted to it during electrolysis?
Molten lead(II) bromide (PbBr₂) is electrolysed using inert (graphite) electrodes.
Name the product formed at the cathode and at the anode.
[1 mark]Explain why solid lead(II) bromide does NOT conduct electricity, but molten lead(II) bromide does.
[1 mark]Concentrated sodium chloride solution (brine) is electrolysed using inert electrodes. Which gases are produced at each electrode?
Dilute copper(II) sulfate (CuSO₄) solution is electrolysed using inert carbon electrodes.
Name the product formed at the cathode and explain why.
[1 mark]Name the product formed at the anode and explain why.
[1 mark]Write the ionic half-equation for the formation of the product at the cathode.
[1 mark]Copper(II) sulfate solution is electrolysed using PURE COPPER electrodes (instead of inert carbon). Which row correctly describes what happens?
A current of 2.0 A is passed through molten sodium chloride for several minutes, using inert electrodes.
Write the half-equation for the reaction at the cathode.
[1 mark]Write the half-equation for the reaction at the anode.
[1 mark]Why are inert (graphite) electrodes used in this electrolysis rather than metal electrodes?
[1 mark]State ONE major industrial use of sodium and ONE major industrial use of chlorine, both produced by electrolysis.
[1 mark]Aluminium is extracted from its molten oxide (Al₂O₃, dissolved in molten cryolite) by electrolysis.
Explain why aluminium is extracted by electrolysis rather than by reduction with carbon.
[1 mark]Write the half-equations for the reaction at the cathode and at the anode during the extraction of aluminium.
[2 marks]Two electrolysis cells, X and Y, are set up in series with the same current passing through both. Cell X contains molten AlCl₃ and cell Y contains molten NaCl, each with inert electrodes. Which row best describes the relative MASS of metal deposited at the cathodes after the same time?