The electrolysis of some other solutions using inert electrodes
1 mark · NormalWhich of the following anions will produce oxygen gas at the anode, rather than a halogen, during electrolysis of an aqueous solution?
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Correct option: Sulfate (SO₄²⁻)
Common mistakes: Selecting a halide ion
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Marking points
B1 · 1 mark · Correctly identifies sulfate (SO₄²⁻).
Worked solution
Sulfate ions are not easily discharged. Oxygen forms at the anode when sulfate is present, not a halogen.