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Question
Explain the following:
On electrolysis of dilute copper (II) sulphate solution, copper is deposited at the cathode but no hydrogen gas evolves there. Explain why?
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Solution
Copper ions (Cu2+) and hydrogen ions (H+) both shift to the cathode, but copper is deposited at the cathode more readily than hydrogen due to its lower position in the electrochemical series. Copper is discharged at the cathode in preference to hydrogen.
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