An ideal monatomic gas undergoes an isothermal expansion. It is correct to affirm that its entropy
A) decreases.
B) remains unchanged.
C) increases.
D) cannot be predicted with the data given.

Question

Quizplus · Accepted Answer

During an isothermal expansion, the temperature remains constant, which means that the internal energy of the gas remains the same. As the gas expands, the volume increases, which means that the number of microstates available to the system also increases. As a result, the entropy of the gas increases. Therefore, the correct option is C) increases.

An Ideal Monatomic Gas Undergoes an Isothermal Expansion