Chapter 20, Problem 20.102P

Interpretation Introduction

Interpretation:

For the oxidation of $Fe$ and $Al$ balanced equation has to be written and using the $\Delta G_f^0$ values it has to be determined whether this process is spontaneous at ${25}^{o}C$.

Concept introduction:

Oxidation: The gain of oxygen or the loss of hydrogen or the loss of an electron in a species during a redox reaction is called oxidation.

Reduction: The loss of oxygen or the gain of hydrogen or gain of an electron in a species during a redox reaction is called reduction.

Free energy (Gibbs free energy) is the term that is used to explain the total energy content in a thermodynamic system that can be converted into work.  The free energy is represented by the letter $\text{G}$.  All spontaneous process is associated with the decrease of free energy in the system.  The standard free energy change ${\text{(ΔG}}^{\text{°}}{}_{\text{rxn}})$ is the difference in free energy of the reactants and products in their standard state.

${\text{ΔG}}^{\text{°}}{}_{\text{rxn}}\text{=}\sum {\text{nΔG}}_{\text{f}}{}^{\text{°}}\text{(Products)-}\sum {\text{nΔG}}_{\text{f}}{}^{\text{°}}\text{(Reactants)}$