Question

Aqueous copper (II) sulphate is electrolysed using copper electrodes.

Which statement about the electrolysis is not correct?

Options

• An oxidation reaction occurs at the positive electrode.

• The current is carried through the electrolyte by ions.

• The positive electrode loses mass.

• The number of copper (II) ions in the electrolyte decreases.

Answer 1

The number of copper (II) ions in the electrolyte decreases.

Explanation:

Copper electrodes act as active electrodes during the electrolysis of aqueous copper (II) sulphate. The purpose of the active electrode is to maintain the ion concentration in the electrolyte, ensuring that the concentration of copper ions in the electrolyte remains constant and the blue colour of the solution stays the same. The claim that there are less copper ions in the electrolyte is false.