In the scheme given below, X and Y , respectively, are

$$\begin{gathered} \text{ Metal halide }\stackrel{\text{ aq. }\mathrm{NaOH}}{\to }\text{ White precipitate }\left(\mathrm{P}\right) +\text{ Filtrate }\left(\mathrm{Q}\right) \\ \mathrm{P}\underset{ }{\stackrel{\text{ aq. }{\mathrm{H}}_2{\mathrm{SO}}_4\text{, } \\ {\mathrm{PbO}}_2\text{ (excess) }}{\underset{\text{ heat }}{\to }}}\mathrm{X}( \mathrm{a} \mathrm{coloured} \mathrm{species} \mathrm{in} \mathrm{soloution}) \\ \mathrm{Q}\underset{\mathrm{Warm}}{\overset{\begin{array}{r}\mathrm{MnO}(\mathrm{OH}{)}_2\\ \text{ Conc. }{\mathrm{H}}_2{\mathrm{SO}}_4\end{array}}{\to }}\mathrm{Y} (\mathrm{gives} \mathrm{blue} -\mathrm{coloration} \mathrm{with} \mathrm{KI}-\mathrm{starch} \mathrm{paper}) \end{gathered}$$

Metal halide is ${\mathrm{MnCl}}_2$
$\begin{array}{l}{\mathrm{MnCl}}_2+\mathrm{NaOH}\stackrel{ }{\to }\mathrm{Mn}{\left(\mathrm{OH}\right)}_2+2\mathrm{NaCl}\\ \text{ (P) (Q)}\end{array}$
$\begin{array}{l}2\mathrm{Mn}{\left(\mathrm{OH}\right)}_2+5{\mathrm{H}}_2{\mathrm{SO}}_4+\mathrm{Pb}{\mathrm{O}}_2\stackrel{ }{\to }{\mathrm{PbSO}}_4+2{\mathrm{HMnO}}_4+4{\mathrm{H}}_2\mathrm{O}\\ \text{ (P) (X)}\end{array}$$\begin{array}{l}2\mathrm{NaCl}+2{\mathrm{H}}_2{\mathrm{SO}}_4+\mathrm{MnO}{\left(OH\right)}_2\stackrel{warm}{\to }{\mathrm{Cl}}_2+{\mathrm{Na}}_2{\mathrm{SO}}_4+{\mathrm{MnSO}}_4+3{\mathrm{H}}_2\mathrm{O}\\ \text{ (Q) (Y) }\end{array}$