Same chapter3 marksDifficulty: Medium
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2 marksDifficulty: Medium
Why is aluminium extracted by electrolysis rather than by reduction with carbon?
Original Khojo Papers practice question — not from a past board paper.
Answer
Aluminium is a highly electropositive metal and its oxide is very stable, so carbon cannot reduce it at any practicable temperature. Electrolysis supplies the electrons directly at the cathode and so achieves the reduction.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
The same reasoning applies to sodium, magnesium and calcium.
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