Assertion `(A):` At the end of electrolysis using `Pt` electrodes, an aqueous solution of `CuSO_(4)` turns colourless.
Reason `(R): CuSO_(4)` chnages to `Cu(OH)_(2)` during electrolysis.

Options

A. If both `(A)` and `(R)` are correct, and `(R)` is the correct explanation of `(A)`.
B. If both `(A)` and `(R)` are correct, but `(R)` is not the correct explanation of `(A)`.
C. If `(A)` is correct, but `(R)` is incorrect.
D. If `(A)` is incorrect, `(R)` is correct.

Answer

c

Explanation

`(A)` is correct. Since `Cu^(2+)` ions are reduced to `Cu` and deposited at cathode. `H_(2)O` is oxidized at anode. `(SO_(4)^(2-)` is not oxidized).
`H_(2)O rarr 2H^(o+)+2e^(-) +(1)/(2) O_(2)`.
`2H^(o+)+SO_(4)^(2-) rarr H_(2)SO_(4)`.
The solution becomes colourless due to the formation of `H_(2)SO_(4)` in solution.
`(R)` is an incorrect statement.