Question

The figure shows an electrolyte of AgCl through which a current is passed. It is observed that 2.68 g of silver is deposited in 10 minutes on the cathode. Find the heat developed in the 20 Ω resistor during this period. Atomic weight of silver is 107.9 g mol−1.
Figure

Answer 1

Heat developed in the 20 Ω resistor is 192 kJ

Explanation:

Given:

Mass of silver deposited, m = 2.68 g

Time, t = 10 minutes = 600 s

Using the formula, m = Zit, we get:

$\text { 2. } 68 \times 10^{-3}=\frac{107.9 \times 10^{-3}}{96500} \times i \times 600$

$i=\frac{2.68 \times 96500}{107.9 \times 600}$

i =3.99

 =4 A

Heat developed in the 20 Ω resistor,

$H=i^{2} R t$

$H=(4)^{2} \times 20 \times 600$

$H=192000 J=192 k J$