Question

A solid body of constant heat capacity
1 $J{/}^{\circ }C$ is being heated by keeping it in contact with reservoirs in two ways.
(i) Sequentially keeping in contact with 2 reservoirs such that each reservoir supplies same amount of heat.
(ii) Sequentially keeping in contact with 8 reservoirs such that each reservoir supplies same amount of heat.
In both cases, the body is brought from initial temperature ${100}^{\circ }C$ to final temperature ${200}^{\circ }C$. Entropy change of the body in two cases respectively is

• A. $ln2,2ln2$
• B. $ln2$, $ln2$
• C. $ln2,4ln2$
• D. $ln2,8ln2$

Answer 1

The correct option is B $ln2$, $ln2$

It is the type of matter which has got fixed shape and volume. The force of attraction between any two molecules of a solid is very large.

But in
Nacl, Diamond, Graphite:

$\Delta S=\int \frac{msdt}{T}=ms\ln \left(\frac{T_f}{T_i}\right)$
$\Delta S=1.\ln \left(\frac{T_f}{T_i}\right)$
$\Delta S$ is state depedent. Its value changes by changing state hence if remain same in two processes. $△S=ln2$