Question

Represent the reaction between lead nitrate and sodium sulfate in aqueous solution?

Answer 1

Hint: Nature of chemical reaction changes depending upon the reactant used in the chemical reaction. Double displacement reaction is defined as a reaction in which components from each reactant will be exchanged with each other to form a new compound.

Complete answer:
The medium used for double displacement reaction is generally water or aqueous medium because it will facilitate the generation of cations and anions. These ions proceed the reaction by switching their places with each other to form two new compounds.
Double displacement further categories as neutralization process, precipitation reaction and reaction which are accomplished with evolution of gases as their product.
Molecular formula of lead nitrate is $Pb{\left( {N{O_3}} \right)_2}$. It is composed of two ions $P{b^{ + 2}}$ and $N{O_3}^{^ - }$.
Molecular formula of sodium sulfate is $N{a_2}S{O_4}$. It is composed of two ions $N{a^ + }$ and $S{O_4}^{ - 2}$
Chemical reaction between lead nitrate and sodium sulfate is expressed as:
$Pb{\left( {N{O_3}} \right)_2}_{\left( {aq} \right)}$$ + $$N{a_2}S{O_4}_{_{\left( {aq} \right)}}$$ \to $$PbS{O_{4\left( s \right)}} \downarrow $$ + $ $2NaN{O_3}_{_{\left( {aq} \right)}}$
From the above chemical equation we see that nitrate ion $N{O_3}^{^ - }$ from lead displaced and attached with sodium ion $N{a^ + }$of sodium sulfate to form a new product known as sodium nitrate $NaN{O_3}$.
Similarly, lead ion $P{b^{ + 2}}$ combines with sulfate ion $S{O_4}^{ - 2}$ to form new compound lead sulfate $PbS{O_{4\left( s \right)}}$. Lead sulfate forms precipitate and settle down in the reaction mixture.
Since, this reaction involves displacement of two ions to form a new product it is known as double displacement reaction.
$ \Rightarrow $ The reaction between lead nitrate and sodium sulfate in aqueous solution is represented as:
$Pb{\left( {N{O_3}} \right)_2}_{\left( {aq} \right)}$$ + $$N{a_2}S{O_4}_{_{\left( {aq} \right)}}$$ \to $$PbS{O_{4\left( s \right)}} \downarrow $$ + $ $2NaN{O_3}_{_{\left( {aq} \right)}}$

Note:
Precipitation produced at the end of the reaction is separated by filtration. After drying we get white crystalline solid of lead sulfate. It is insoluble in aqueous medium and tends to sink down in water. It is highly irritant to the skin, eye, and mucous membrane of the gastrointestinal tract.