Question

Mercury cathode cannot be used to obtain alkali metal in fused state because

Answer 1

Hello...

Alkali metals are excellent reducing agents. Mercury can be used as Cathode where Alkali metal get Accumulated at the cathode, but the problem is that the alkali accumulated at the cathode readily reacts with Mercury to form an Amalgam. So the Alkali metal cannot be recovered Easily. That's why mercury can't be used to obtain alkali metal.

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