Chapter 10, Problem 9CO

Interpretation Introduction

Interpretation:

The spontaneity of a process depends on several factors; one of the several factors is entropy. When the change in the total entropy is positive, the process is said to be spontaneous.

Concept introduction:

• Entropy is referred to as the 'state of disorder' of a system. Also, entropy is a measure of the energy of atoms and molecules in a process and can be defined in terms of statistical probabilities of a system or in terms of the other thermodynamic quantities.
• When the change in the total entropy is negative, the process is said to be non-spontaneous, in contrast, when the change in entropy is positive, the process is said to be spontaneous.

$\Delta S_{total}=\Delta S_{system}+\Delta S_{surroundings}$

• The change in entropy occurs during phase transitions, precipitation reactions etc.
• The change in entropy of the system is defined as the difference between the entropies of the final and initial states:

$\Delta S = S_f - S_i.$