A-LevelChemistryElectrochemistry9701/12 · May/June 2020 · Q101 Mark

In which reaction does an element undergo the largest change in oxidation number?

ACl2 + 2OH¯ → OCl¯ + Cl¯ + H2O

B3Cl2 + 6OH¯ → ClO3¯ + 5Cl¯ + 3H2O

CCr2O7²⁻ + 6Fe²⁺ + 14H⁺ → 2Cr³⁺ + 6Fe³⁺ + 7H2O

D3MnO4²⁻ + 4H⁺ → MnO2 + 2MnO4¯ + 2H2O

✓ Correct answer

B: 3Cl2 + 6OH¯ → ClO3¯ + 5Cl¯ + 3H2O

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Topic: Electrochemistry, A-Level Chemistry (syllabus 9701). Multiple choice, 1 mark.
Source: A-Level Chemistry, May/June 2020 Paper 1 Variant 2, question 10.

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