Question

$0.2964g$ of $Cu$ was deposited on passage of a current of $0.5amp$ for $30\min$ , through a solution of copper sulphate. Calculate the atomic weight of $Cu$ .
Give your answer by rounding off the value to two significant figures.

Answer 1

Answer: 64

Given:
Weight of copper deposited $w=0.2964g$
Current $i=0.5amp$
Time $t=30\min$
For, $C{u}^{2+}\to Cu$ .
From Faraday's law of electrolysis:
$w=Zit$
$Z=\frac{M_{Cu}}{2\times 96500}$
$0.2964=\frac{M_{Cu}}{2\times 96500}\times 0.5\times 30\times 60$
$M_{Cu}=\mathrm{63.56.}$