Chapter 15, Problem 23QAP

Interpretation Introduction

Interpretation:

Whetherany ${\text{PbCl}}_{\text{2}}$ is crystallized out or not needs to be determined, if1 g mass of ${\text{PbCl}}_{\text{2}}$ is dissolved in 1.0 L volume of hot water and the solution is cooled to ${\text{25}}^{\text{0}}\text{C}$.

Concept introduction:

The equilibrium reaction for ${\text{PbCl}}_{\text{2}}$ to produce one mole of ${\text{Pb}}^{\text{2+}}$ and two moles of ${\text{Cl}}^{2-}$ is shown as follows:

${\text{PbCl}}_{\text{2}}\left(\text{s}\right)\rightleftharpoons {\text{Pb}}^{\text{2+}}\left(\text{aq}\right){\text{+2Cl}}^{2-}\left(\text{aq}\right)$

Let, s is molar solubility of ${\text{PbCl}}_{\text{2}}$. So, s moles of ${\text{PbCl}}_{\text{2}}$ dissolve to gives s moles of ${\text{Pb}}^{\text{2+}}$ ions and 2s moles of ${\text{Cl}}^{2-}$ ions.