An electric current is passed through silver nitrate
solution using silver electrodes and 10.79 g of silver was
found to be deposited on the cathode. If the same amount
of electricity is passed through copper sulphate solution
using copper electrodes, the weight of copper deposited
on the cathode is

Options

A. 6.4 g
B. 12.8 g
C. 1.6 g
D. 3.2 g

Answer

D

Explanation

Number of equivalents of silver formed =Number of equivalents of copper formed
In `AgNO_3,` Ag is in + 1 oxidation state.
In `CuSO_4,` Cu is in + 2 oxidation state.
Equivalent weight of Ag =`108/1=108`
Equivalent weight of Cu= 63.5/2=31.8
`w_1/w_2=E_1/E_2` `implies` `10.79/w_(Cu)=108/31.8`
`w_(cu)=(10.79xx31.8)/108` =3.2 g