O-LevelChemistryElectrolysis5070/11 · May/June 2025 · Q151 Mark

The diagram shows an electrolysis experiment using inert electrodes. Which row shows what happens to the concentration of the electrolyte in L and in M as the electrolysis proceeds?

This question uses a diagram from the original paper, which isn't shown here. Open the full paper from the past papers archive to see it.

Ax | x | key x = concentration does not stay constant

Bx | ✓ | ✓ = concentration stays constant

C✓ | x | key x = concentration does not stay constant

D✓ | ✓ | ✓ = concentration stays constant

✓ Correct answer

A: x | x | key x = concentration does not stay constant

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Topic: Electrolysis, O-Level Chemistry (syllabus 5070). Multiple choice, 1 mark.
Source: O-Level Chemistry, May/June 2025 Paper 1 Variant 1, question 15.

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