Question

A dilute aqueous solution of `Na_(2)SO_(4)` is electrolysed using platinum electrodes. The products at the anode and cathode are
A. `O_(2),H_(2)`
B. `S_(2)O_(8)^(2-),Na`
C. `O_(2),Na`
D. `S_(2)O_(8)^(2-),H_(2)`

Answer 1

Correct Answer - A
`H_(2)O` is more readily reduced at cathode than `Na^(+).` it is also more readily oxidized at anode than `SO_(4)^(2-)`. Hence, the electrode reactions are
`2H_(2)O+2e^(-)toH_(2)uarr+2OH^(-)`
[at cathode], `H_(2)O to (1)/(2)O_(2)uarr+2H^(+)+2e^(-)` [at anode].