8 A solid of constant heat capacity C is heated by keeping i

8. A solid of constant heat capacity C is heated by keeping it in contact with reservoirs in two ways: (i) Sequentially keeping in contact with 2 reservoirs such that each supplies the same amount of heat (ii) Sequentially keeping in contact with 8 reservoirs such that each supplies the same amount of heat. In both cases, the body is brought from an initial temperature of 100 K to a final temperature of 200 K. The entropy change of the body in the two cases respectively is: (a) (C ln2, 4C ln2) (b) (C ln2, C lin?) (c) (C In2, 2C In2) (d) (2C ln2, 8C ln?)

Solution

We know that similar to internal energy and enthalpy, entropy is also a state function, so entropy does not depend on how the process is carried out or how the system arrived at the state. Since initial and final temperature (state) remains same in both the process hence entropy will also be same. Correct choice is (2)