Chapter 18.4, Problem 38LC

Interpretation Introduction

Interpretation: The explanation for which two values should be compared to predict whether a precipitate is formed or not by mixing two solutions is to be stated.

Concept Introduction: The expression representing the product of the concentrations of the ions each raised to the power (equal to their stoichiometric coefficient) in the dissociation equation is termed as solubility product constant $\left({\text{K}}_{\text{sp}}\right)$ .

Answer to Problem 38LC

The reaction quotient (Q) and solubility product constant $\left({\text{K}}_{\text{sp}}\right)$ values should be compared to predict whether a precipitate is formed or not by mixing two solutions.

Explanation of Solution

If $\text{Q}>{\text{K}}_{\text{sp}}$ then there occurs precipitation on mixing of the two solutions whereas if $\text{Q}<{\text{K}}_{\text{sp}}$ then there will be no formation of the precipitate on mixing of the two solutions. Thus, the value of the reaction quotient (Q) and solubility product constant $\left({\text{K}}_{\text{sp}}\right)$ tells whether a precipitate is formed or not by mixing two solutions.