Question

A current of $19296\, C$ is passed through an aqueous solution of copper sulphate using copper electrodes. What is the mass (in $g$ ) of copper deposited at the cathode? (Molar mass of $Cu =63.5 \,g \,mol ^{-1}$ )

• A. 3.17
• B. 1.58
• C. 6.35
• D. 0.79

Answer 1

Answer: (C)

Given,

Charge used $=19296\, C$

Molar mass of $Cu =63.5$

$\because Cu$ in $CuSO _{4}$ has $Cu ^{2+}$ charge means:

$2 \times 96500\, C$ of charge give $=63.5 \,g$ of $Cu$

Thus, $19296 \,C$ of charge give $=\frac{63.5 \times 19296}{2 \times 96500}$

$=6.35 \,g$ of copper $( Cu )$.