Question

Name from the list of substances given below, that would be used to prepare each of the salts named in parts (a) to (d).

(The substances are copper, lead, sodium, zinc, copper oxide, lead carbonate solution, $\mathrm{dil}.\mathrm{HCl}$, $\mathrm{dil}.{\mathrm{HNO}}_3$ and $\mathrm{dil}.{\mathrm{H}}_2{\mathrm{SO}}_4$).

(d) Lead sulphate

Answer 1

1. Lead carbonate $\left({\mathrm{PbCO}}_3\right)$ solution reacts with dilute nitric acid $\left(\mathrm{dil}.{\mathrm{HNO}}_3\right)$ to form lead nitrate $\left[\mathrm{Pb}{\left({\mathrm{NO}}_3\right)}_2\right]$, water $\left({\mathrm{H}}_2\mathrm{O}\right)$ and carbon dioxide $\left({\mathrm{CO}}_2\right)$ gas.

2. The chemical equation representing the reaction is written below:

${\mathrm{PbCO}}_3+2{\mathrm{HNO}}_3\to \mathrm{Pb}{\left({\mathrm{NO}}_3\right)}_2+{\mathrm{H}}_2\mathrm{O}+{\mathrm{CO}}_2\left(\mathrm{g}\right)$

3. The lead nitrate obtained is then treated with dilute sulphuric acid $\left(\mathrm{dil}.{\mathrm{H}}_2{\mathrm{SO}}_4\right)$ and a white precipitate of lead sulphate $\left({\mathrm{PbSO}}_4\right)$ is formed along with nitric acid $\left({\mathrm{HNO}}_3\right)$.

4. The chemical equation representing the reaction is written below:

$\mathrm{Pb}{\left({\mathrm{NO}}_3\right)}_2+{\mathrm{H}}_2{\mathrm{SO}}_4\to {\mathrm{PbSO}}_4+2{\mathrm{HNO}}_3$

Hence, to prepare lead sulphate, the substance required is lead carbonate solution, $\mathrm{dil}.{\mathrm{HNO}}_3$ and $\mathrm{dil}.{\mathrm{H}}_2{\mathrm{SO}}_4$