Chemistry · May / June 2025 · Paper 11 · Question 15

The diagram shows an electrolysis experiment using inert electrodes. [diagram: two beakers L and M connected in series with a battery and inert electrodes. Beaker L contains aqueous copper(II) sulfate electrolyte. Beaker M contains dilute sulfuric acid electrolyte.] Which row shows what happens to the concentration of the electrolyte in L and in M as the electrolysis proceeds? | | L | M | |---|---|---| | A | x | x | | B | x | ✓ | | C | ✓ | x | | D | ✓ | ✓ | key ✓ = concentration stays constant x = concentration does not stay constant

1. AL: x, M: x
2. BL: x, M: ✓
3. CL: ✓, M: x
4. DL: ✓, M: ✓

As printed in the paper