Same chapter3 marksDifficulty: Medium
During the electrolysis of aqueous copper sulphate using copper electrodes, state what happens at each electrode and why the colour of the solution does not change.
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2 marksDifficulty: Medium
Why is copper refined electrolytically rather than chemically?
Original Khojo Papers practice question — not from a past board paper.
Answer
Electrolytic refining gives copper of very high purity, which is what electrical conductors need, and the impurities separate cleanly: the more active metals stay in solution and the less active ones fall as anode mud, from which silver and gold can be recovered.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
Chemical methods leave traces of impurity that raise the resistance of the metal appreciably.
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