Tue February 15, 2011 By: Srishti Aggarwal

Why is that aluminium cannot be obtained by electrolysis of an aqueous solution of a salt of aluminium?

Expert Reply
Fri February 18, 2011
Dear Student
Aluminium cannot be produced by the electrolysis of an aluminium salt dissolved in water because of the high reactivity of aluminium with the protons of water and the subsequent formation of hydrogen. As in aqueous solution, protons (H+) are preferentially reduced before Al3+ ions, leading to hydrogen evolution, the reduction of Al3+ requires to perform the electrolysis in a molten aluminium salt in the absence of water.
We hope that clarifies your query.
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