Chapter 20.2, Problem 20.3BFP

Interpretation Introduction

Interpretation: Whether oxidation of $\text{FeO}\left(s\right)$ to ${\text{Fe}}_{\text{2}}{\text{O}}_{\text{3}}\left(s\right)$ takes place spontaneously at 298 K or not, needs to be identified.

Concept Introduction: The relation between change in enthalpy of reaction and change in entropy of surrounding is as follows:

  $\Delta S_{\text{surrounding}}=-\frac{\Delta H_{\text{reaction}}}{T}$

Here, T is the absolute temperature.

From the change in entropy of reaction and that of surrounding, the change in entropy of the universe can be estimated as follows:

  $\Delta S_{\text{universe}}=\Delta S_{\text{reaction}}+\Delta S_{\text{surrounding}}$

For a reaction to be spontaneous, the change in entropy of the universe is always positive.