Q33 / 160 · TS EAMCET 2006 · Chemistry
Assertion (A) : A current of $96.5 \mathrm{~A}$ is passed into aqueous $\mathrm{AgNO}_3$ solution for $100 \mathrm{~s}$. The weight of silver deposited is $10.8 \mathrm{~g}$ (At. wt. of $\mathrm{Ag}=108)$Reason (R) : The mass of a substance deposited during the electrolysis of an electrolyte is inversely proportional to the quantity of electricity passing through the electrolyte.
The correct answer is :
- ABoth (A) and (R) are true and (R) is the correct explanation of (A)
- BBoth (A) and (R) are true but (R) is not the correct explanation of (A)
- Correct answerC(A) is true but (R) is false
- D(A) is false but (R) is true
Solution
$i=96.5 \mathrm{~A}, t=100 \mathrm{~s}$
$w=108$
$Q=i t$
$Q=96.5 \times 100=9650 \mathrm{C}$
$\because 96500$ coulomb deposited wt. of $\mathrm{Ag}=108 \mathrm{~g}$
$\therefore 9650$ coulomb deposited wt. of Ag
$=\frac{108 \times 9650}{96500}$
So, statement $\mathbf{A}$ is true but $\mathbf{R}$ is false. $\mathbf{R}$ is false because mass of substance deposited is directly proportional to the quantity of electricity.
Hence, the correct answer is option: 'C'.