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O-LevelChemistryElectrolysis5070/12 · Oct/Nov 2021 · Q141 Mark

Which statement about the electrolysis of solutions is correct?

ADuring the electrolysis of concentrated aqueous sodium chloride solution, hydrogen is produced at the cathode.
BDuring the electrolysis of dilute sulfuric acid, oxygen is produced at the cathode.
CWhen aqueous copper(II) sulfate is electrolysed, the reaction taking place at the cathode is Cu+(aq) + e⁻ → Cu(s).
DWhen aqueous copper(II) sulfate is electrolysed using copper electrodes, the mass of the anode at the end of the reaction will be greater than at the beginning.

✓ Correct answer

A: During the electrolysis of concentrated aqueous sodium chloride solution, hydrogen is produced at the cathode.

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About this question

Topic
Electrolysis, O-Level Chemistry (syllabus 5070). Multiple choice, 1 mark.
Source
O-Level Chemistry, Oct/Nov 2021 Paper 1 Variant 2, question 14.

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