Question

In a solution of $CuS{O}_4$ how much time will be, required to precipitate $2g$ copper by $0.5$ ampere current

• A. 12157.48 sec
• B. 102 sec
• C. 510 sec
• D. 642 sec.

Answer 1

Answer: (A)

$C{u}^{3+}+\underset{2mole,2F}{2e^{-}}\to \underset{1mole,63.5gm}{\mathrm{Cu}}$
To deposit $63.5gm$ of copper, electricity needed
$=2\times 96500C$
To deposit $2gm$ of copper, electricity needed
$=2\times \frac{96500}{63.5}\times 2$
$=6078.74C$
$Q=6078.74C$
$I=0.5$ ampere
$Q=It$
$t$ (in seconds) $=\frac{Q}{I}=\frac{6078.74}{0.5}$
$=12157.48s$