O-LevelChemistryElectrolysis5070/11 · May/June 2021 · Q201 Mark

In which equations is the change in the underlined species correct? 1 CH₄ + 2O₂ → CO₂ + 2H₂O -oxidation 2 2H₂S + SO₂ → 3S + 2H₂O -reduction 3 BrO₃⁻ + 5Br⁻ + 6H⁺ → 3Br₂ + 3H₂O -reduction

A1 only

B2 only

C1 and 3

D2 and 3

✓ Correct answer

A: 1 only

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Topic: Electrolysis, O-Level Chemistry (syllabus 5070). Multiple choice, 1 mark.
Source: O-Level Chemistry, May/June 2021 Paper 1 Variant 1, question 20.

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