Chapter 18, Problem 8SAQ

Interpretation Introduction

Introduction: To calculate the change in standard entropy $\Delta G_{\text{rxn}}^{°}$ from standard free energy of formation $\Delta G_{\text{f}}^{º}$, subtract the standard entropy of formation $\Delta G_{\text{f}}^{º}$ of the reactants multiplied by their stoichiometric coefficients from the standard free energy of formation $\Delta G_{\text{f}}^{º}$ of the products multiplied by their stoichiometric coefficients.

Mathematically, it can be expressed as

$\Delta G_{}^{°}=\Sigma n_{\text{p}}\Delta G_{\text{f}}^{º}\left(\text{products}\right)-\Sigma n_r\Delta G_{\text{f}}^{º}\left(reactants\right)$

Here, $n_{\text{p}}$ represents the stoichiometric coefficients of the products, n_r represents the stoichiometric coefficients of the reactants, and $\Delta G_{\text{f}}^{º}$ represents the standard free energy of formation.