O-LevelChemistryElectrolysis5070/11 · Oct/Nov 2017 · Q141 Mark

Aluminium is produced by the electrolysis of molten aluminium oxide. What is the correct equation for the reaction at the positive electrode?

AAl → Al³⁺ + 3e⁻

BAl³⁺ + 3e⁻ → Al

CO₂ + 4e⁻ → 2O²⁻

D2O²⁻ → O₂ + 4e⁻

✓ Correct answer

D: 2O²⁻ → O₂ + 4e⁻

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Topic: Electrolysis, O-Level Chemistry (syllabus 5070). Multiple choice, 1 mark.
Source: O-Level Chemistry, Oct/Nov 2017 Paper 1 Variant 1, question 14.

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