Chapter 16, Problem 16.71SP

(a)

Interpretation Introduction

Interpretation:

The values of $\Delta H,\Delta S$ and $\Delta G$ for the process of twofold expansion of $1\text{ mol}$ of ideal gas has to be described.

Concept Introduction:

Enthalpy change is $\Delta H$ and entropy change is $\Delta S.$

$\Delta S$ for the process of expansion or compression of gas is determined as,

$\Delta S=\text{ R ln}\frac{V_{final}}{V_{inital}}$

Gibbs free energy change is $\Delta G.$ $\Delta H,\Delta S$ and $\Delta G$ are related as,

$\Delta G=\Delta H-T\Delta S$

(b)

Interpretation Introduction

Interpretation:

Second law of thermodynamics illustrated by the process of twofold expansion of ideal gas has to be described.

Concept Introduction:

• Second law of Thermodynamics is stated as follows,

“ In any spontaneous process Entropy of the Universe always increases.”

• Entropy of the universe is referred as total entropy which is the sum of entropy of the system and entropy of surroundings.

$\Delta S_{total}=\Delta {\text{S}}_{sys}+\Delta S_{surr}$