Chapter 3, Problem 3.63E

Interpretation Introduction

Interpretation:

Whether the $\Delta S$ value for the reaction,

$\text{Ba}{\left(\text{OH}\right)}_2\cdot 8{\text{H}}_{\text{2}}\text{O}\left(\text{s}\right)+2{\text{NH}}_{\text{4}}\text{SCN}\left(\text{s}\right)\to \text{Ba}{\left(\text{SCN}\right)}_2\left(\text{s}\right)+2{\text{NH}}_3\left(\text{g}\right)+10{\text{H}}_{\text{2}}\text{O}\left(l\right)$,

is positive or negative is to be stated. Whether the answer supports the spontaneity of the reaction or not is also to be stated.

Concept introduction:

The change in entropy of a reaction is given by the formula written below.

$\Delta S{°}_{\text{rxn}}^{}={\displaystyle \sum _{\text{Products}}S°}-{\displaystyle \sum _{\text{Reactants}}S°}$

Thus, the molar entropy change of a reaction is taken as the value obtained by subtracting the sum of the entropy of reactants from the sum of the entropy of products.