Chapter 20, Problem 20.32P

Interpretation Introduction

Interpretation:

For the given reaction, ${\text{S}}^{\text{o}}$ of $C{l}_{2}O\left(g\right)$ has to be determined.

Concept Introduction:

Entropy $\text{S}$: it is used to describe the disorder. It is the amount of arrangements possible in a system at a particular state. ${\text{ΔS}}_{\text{univ}}={\text{ΔS}}_{\text{sys}}+{\text{ΔS}}_{\text{surr}}$

Entropy is a thermodynamic quantity, which is the measure of randomness in a system.  The term entropy is useful in explaining the spontaneity of a process.  For all spontaneous process in an isolated system there will be an increase in entropy.  Entropy is represented by the letter ‘S’. It is a state function.  The change in entropy gives information about the magnitude and direction of a process.  The entropy of one mole of substance at a given standard state is called standard molar entropy ($S^o$).

Entropy is the measure of randomness in the system. The entropy change in a reaction is the difference in entropy of the products and reactants ${\text{(ΔS}}_{\text{rxn}}\text{)}$ can be calculated by the following equation.

${\text{ΔS}}_{\text{rxn}}{\text{ = S}}_{\text{Products}}-{\text{ S}}_{\text{reactants}}$

Where,

  ${\text{S}}_{\text{reactants}}$ is the entropy of the reactants.

  ${\text{S}}_{\text{Products}}$ is the standard of the products.