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Question
On passing 1.5 F charge, the number of moles of aluminium deposited at cathode are _______ [Molar mass of Al = 27 gram mol–1]
(A) 1.0
(B) 13.5
(C) 0.50
(D) 0.75
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Solution
(C) 0.50
The half reaction for the reduction of Al3+ ion is
Al3+ + 3e– → Al
The reaction indicate that 1 mole of Al is produced by the passage of 3 mole electrons. The charge of 3 mole electrons is 3 faraday.
3 F of charge produces 1 mole of Al.
1.5 F of charge produces 0.50 mole of Al.
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