Question

How much time is required to deposit $1\times {10}^{-3}$cm thick layer of silver(density is $1.05$g $c{m}^{-3}$) on a surface of area $100$ $c{m}^2$ by passing a current of $5$A through $AgN{O}_3$ solution?

• A. $125$s
• B. $115$s
• C. $18.7$s
• D. $27.25$s

Answer 1

The correct option is C $18.7$s

We know, $Density=\frac{Mass}{Volume}$

Here, Mass of $Ag$ in coated layer=$Volume\times density$

$=1\times {10}^3\times 100\times 1.05$

$=0.105g$

Now, $W=\frac{1\times t\times Eq.wt.}{96500}$

$⟹t=\frac{W\times 96500}{I\times Eq.wt.}$

$=\frac{0.105\times 96500}{5\times 108}=18.7s$