Two platinum electrodes were immersed in a solution of `CuSO_(4)` and electric current was passed through the solution. After some time, it was found that colour of `CuSO_(4)` disappeared with evolution of gas at the electrode. The colourless solution contains.

Options

A. Platinum sulphate
B. Copper hydroxide
C. Copper sulphate
D. Sulphuric acid

Answer

d

Explanation

`CuSO_(4)(aq) overset(El ectrolysis)rarrCu^(2+)(aq)+SO_(4)^(2-)(aq)`
At cathode`:Cu^(2+)(aq)+2e^(-) rarr Cu(` reduction `)`
The blue colour of `CuSO_(4)` disappears due to the deposition of `Cu` on `Pt` electrode.
At anode `: H_(2)O rarr 2H^(o+)+2e^(-)+(1)/(2)O_(2)(g)`
Since oxidation potential of `SO_(4)^(2-)`, so oxidation of `H_(2)O` occurs and `O_(2)(g)` is evolved at anode.
The colourless solution is due to the formation of `H_(2)SO_(4)` as follows `:`
`2H^(o+)(` from anode `)+SO_(4)^(2-) rarr H_(2)SO_(4)`