Chapter 20.3, Problem 20.7AFP

(a)

Interpretation Introduction

Interpretation: Whether the given reaction is spontaneous or not at 298 K needs to be estimated.

Concept Introduction: A reaction is said to be spontaneous if the value of the change in Gibbs free energy is negative. The relation between the change in Gibbs free energy, the change in enthalpy, and change in entropy at a given temperature is represented as follows:

  $\Delta G=\Delta H-T\Delta S$

Here, T is the absolute temperature.

(b)

Interpretation Introduction

Interpretation: Whether the reaction will be more or less spontaneous at higher temperature needs to be identified.

Concept Introduction: A reaction is said to be spontaneous if the value of change in Gibbs free energy is negative. The relation between the change in Gibbs free energy, enthalpy, and entropy at a given temperature is represented as follows:

  $\Delta G=\Delta H-T\Delta S$

Here, T is the absolute temperature.

(c)

Interpretation Introduction

Interpretation: The value of change in Gibbs free energy needs to be calculated at ${500}^{\text{ o}}\text{C}$ for the given change in entropy and enthalpy values.

Concept Introduction: A reaction is said to be spontaneous if the value of change in Gibbs free energy is negative. The relation between the change in Gibbs free energy, change in enthalpy and change in entropy at a given temperature is represented as follows:

  $\Delta G=\Delta H-T\Delta S$

Here, T is the absolute temperature.