Chapter 7.1, Problem 7.5Q

Interpretation Introduction

Interpretation:

The reaction will be spontaneous, nonspontaneous, or temperature dependent if $\Delta H$ is positive and $\Delta S$ is negative has to be predicted with reasoning.

Concept Introduction:

Reaction can be said to be spontaneous, nonspontaneous or temperature dependent by considering the free energy change.  Free energy is symbolized as $\Delta G$.  The equation for free energy can be given as,

    $\Delta G=\Delta H-T\Delta S$

If the value of $\Delta G$ is negative, then the reaction will be spontaneous and if the value of $\Delta G$ is positive, then the reaction will be nonspontaneous.  Apart from this another condition is that if both $\Delta H$ and $\Delta S$ are either positive or negative, the reaction will be temperature dependent.