Chapter 9.2, Problem 27PP

Interpretation Introduction

Interpretation:

The balanced chemical equation for the given double displacement reaction needs to be determined.

Concept introduction:

The type of replacement reaction in which exchange of ions takes place between two compounds of the reaction is known as double displacement reaction. One example of this type of reaction is,

${\text{Ca(OH)}}_2(aq)+2\text{HCl(}aq\text{)}\to {\text{CaCl}}_2(aq)+2{\text{H}}_{\text{2}}\text{O}$

Answer to Problem 27PP

The balanced chemical equation is,

$\begin{array}{l}{\text{Na}}_{\text{2}}{\text{C}}_{\text{2}}{\text{O}}_{\text{4}}(aq)+{\text{Pb(NO}}_{\text{3}}{\text{)}}_{\text{2}}(aq)\to {\text{PbC}}_{\text{2}}{\text{O}}_{\text{4}}(s)+2{\text{NaNO}}_{\text{3}}(aq)\\ \text{Sodium}\text{oxalate }\text{lead(II)}\text{nitrate}\text{lead}\text{(II)}\text{oxalate}\text{Sodium}\text{nitrate}\end{array}$

Explanation of Solution

Reaction of aqueous sodium oxalate and aqueous lead (II) nitrate produces solid lead (II) oxalate and aqueous sodium nitrate. In the reaction, exchange of ions of both the reactants occurs. So, the reaction is double displacement reaction.

$\begin{array}{l}{\text{Na}}_{\text{2}}{\text{C}}_{\text{2}}{\text{O}}_{\text{4}}(aq)+{\text{Pb(NO}}_{\text{3}}{\text{)}}_{\text{2}}(aq)\to {\text{PbC}}_{\text{2}}{\text{O}}_{\text{4}}(s)+{\text{NaNO}}_{\text{3}}(aq)\\ \text{Sodium}\text{oxalate }\text{lead(II)}\text{nitrate}\text{lead}\text{(II)}\text{oxalate}\text{Sodium}\text{nitrate}\end{array}$

The above equation is not a balanced reaction. So, the balanced chemical equation is as follows:

$\begin{array}{l}{\text{Na}}_{\text{2}}{\text{C}}_{\text{2}}{\text{O}}_{\text{4}}(aq)+{\text{Pb(NO}}_{\text{3}}{\text{)}}_{\text{2}}(aq)\to {\text{PbC}}_{\text{2}}{\text{O}}_{\text{4}}(s)+2{\text{NaNO}}_{\text{3}}(aq)\\ \text{Sodium}\text{oxalate }\text{lead(II)}\text{nitrate}\text{lead}\text{(II)}\text{oxalate}\text{Sodium}\text{nitrate}\end{array}$

Conclusion

In the double displacement reaction, exchange of ions of both the reactants occurs.