Chapter 3, Problem 56E

Interpretation Introduction

Interpretation: The iodide of the given cations present in the solution that precipitates out first from the solution is to be determined. Also the concentration of the iodide ion required to initiate the precipitation is to be calculated.

Concept introduction: The solubility product constant of a compound is the product of solubility of its ions raised to the power of their stoichiometric coefficients.

To identify: The first precipitating species from the solution of $2.0\times {10}^{-4}\text{M}$

$\text{AgI}$ and $1.5\times {10}^{-3}\text{M}$

${\text{PbI}}_2$ and the concentration of ${\text{I}}^{-}$ needed for the precipitation.