Aqueous copper (II) sulphate is electrolysed using copper electrodes. Which statement about the electrolysis is not correct?
(a) An oxidation reaction occurs at the positive electrode.
(b) The current is carried through the electrolyte by ions.
(c) The positive electrode loses mass.
(d) The number of copper (II) ions in the electrolyte decreases.
(d) The number of copper (II) ions in the electrolyte decreases.
Explanation:
Cu2+ ions deposited at the cathode are replaced by Cu2+ ions produced at the anode, so the overall Cu2+ concentration stays constant.
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