Chapter 17, Problem 112IL

(a)

Interpretation Introduction

Interpretation: The chloride salt of lead is converted to its chromate salt to test its presence, the reason has to be confirmed.

Concept introduction: Metal ions present in a solution can be identified by a set procedure known as qualitative analysis. Different metal ions show different reactions with different reagent and thus either through the color of the precipitate formed or by smell the gas evolved the metal ion present can be identified.

Some metal ions when present in an aqueous solution containing anions or neutral species called Lewis base or ligands having a tendency to donate electron pairs to metal ions then complex ion formation will take place. Complex ions are stable and thus formation of these increase the solubility of the salt containing the metal ions same as in complex ions.

Example of metal ions that form complex ions includes ${\text{Ag}}^{+}$,${\text{Cd}}^{2+}$,${\text{Fe}}^{2+}$,${\text{Zn}}^{2+}$,${\text{Ni}}^{2+}$ etc.

Example of Lewis bases includes,${\text{NH}}_3$,${\text{OH}}^{-}$ etc.

(b)

Interpretation Introduction

Interpretation: The presence of ${\text{Ag}}^{\text{+}}$ and ${\text{Cu}}^{\text{2+}}$ ions in the solution has to be confirmed using complex ion  method.

Concept introduction: Metal ions present in a solution can be identified by a set procedure known as qualitative analysis. Different metal ions show different reactions with different reagent and thus either through the color of the precipitate formed or by smell the gas evolved the metal ion present can be identified.

Some metal ions when present in an aqueous solution containing anions or neutral species called Lewis base or ligands having a tendency to donate electron pairs to metal ions then complex ion formation will take place. Complex ions are stable and thus formation of these increase the solubility of the salt containing the metal ions same as in complex ions.

Example of metal ions that form complex ions includes ${\text{Ag}}^{+}$,${\text{Cd}}^{2+}$,${\text{Fe}}^{2+}$,${\text{Zn}}^{2+}$,${\text{Ni}}^{2+}$ etc.

Example of Lewis bases includes,${\text{NH}}_3$,${\text{OH}}^{-}$ etc.