Chapter 18, Problem 17QP

Interpretation Introduction

Interpretation:

The given substances are to be arranged in the increasing order of entropy.

Concept introduction:

For the chemical reaction:

$\text{aA+bB}\to \text{cC+dD}$

The change in entropy is calculated as below:

$\Delta {\text{S}}^{\circ }{}_{\text{rxn}}{\text{ = dΔS}}^{\text{o}}\left(\text{D}\right)\text{+c}\text{}{\text{ΔS}}^{\text{o}}\left(\text{C}\right){\text{-aΔS}}^{\text{o}}\left(\text{A}\right){\text{-bΔS}}^{\text{o}}\left(\text{B}\right)$

Here, ${\text{ΔS}}^{\text{o}}$

is the change in entropy for the reaction.

Entropy is a measure of disorder or randomness within the molecule of a system. The entropy of a substance increases with the increase in the molecular weight, complexity and temperature. It also increases with the decrease in pressure and concentration.