One Faraday of electricity is passed through molten `Al_(2)O_(3)`, aqueous solution of `CuSO_(4)` and molten NaCl taken in three different electrolytic cells connected in series . The mole ratio of Al , Cu and Na deposited at the respective cathode is :

Options

A. `2: 3: 6`
B. `6 : 2 : 3`
C. `6 : 3 : 2 `
D. `1 : 2 : 3`

Answer

A

Explanation

(a) `Al^(3+)+underset(1F)underset(3F)3e^(-) to nderset(1//3"mol")underset(1"mol")(Al)`
`Cu^(2+)+underset(1F)underset(2F)2e^(-) to underset(1//2mol)underset(1mol)(Cu)`
`Na^(+)+underset(1F)e^(-) to underset(1mol)(Na)`
Mole ratio of Al, Cu and Na deposited at the respective cathodes is :
`1//3 : 1//2 : 1//1 "or" 2:3:6`