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Positive-electrode half equation
What is the half equation for the reaction at the positive electrode when aqueous calcium chloride solution is electrolysed? Tick one box.
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Marking points
- 1 Selects 2 Cl⁻ → Cl₂ + 2 e⁻.
Why this answer loses marks
The positive electrode gains electrons.
At the anode, chloride ions are oxidised and electrons are released.