Chapter 20.3, Problem 20.4AFP

Interpretation Introduction

Interpretation: The value of change in Gibbs free energy of reaction needs to be calculated from the change in enthalpy of reaction and change in entropy of the reaction at 298 K.

Concept Introduction:

The change in enthalpy and change in entropy of a reaction can be calculated using the change in enthalpy of formation and entropy of components respectively from the thermodynamic table (at 298 K).

These two values do not depend on T thus, the value will be the same for all the temperature values. Here, the change in Gibbs free energy of reaction changes with T thus, it is calculated as follows:

  $\Delta G=\Delta H-T\Delta S$

Here, $\Delta H$ is the change in enthalpy, $\Delta S$ is the change in entropy and T is temperature.