Question

How much metal will be deposited when a current of $12$ ampere with $75\%$ efficient is passed through the cell for $3$h? (Given: $Z=4\times {10}^{-4}$)

• A. $32.4$g
• B. $38.8$g
• C. $36.0$g
• D. $22.4$g

Answer 1

The correct option is B $38.8$g

Faraday's First Law of Electrolysis states that only, According to this law, the chemical deposition due to the flow of current through an electrolyte is directly proportional to the quantity of electricity (coulombs) passed through it.
Given,
Efficiency=$75$
$I=5A$
$t=5h$
According to Faraday's first law of electrolysis,
$W=Z\times I\times t$

$=4\times {10}^{-4}\times 12\times \frac{75}{100}\times 3\times 3600=38.8g$

Hence option (B) is correct.