Write any four oxidising and four reducing properties of H₂O₂.

Oxidising properties :
1) H₂O₂ oxidises black PbS to white PbSO₄
$\mathrm{PbS}+4{\mathrm{H}}_2{\mathrm{O}}_2\stackrel{ }{\to }{\mathrm{PbSO}}_4+4{\mathrm{H}}_2\mathrm{O}$
2) It oxidises iodide ion to iodine.
$2\mathrm{KI}+{\mathrm{H}}_2{\mathrm{O}}_2\stackrel{ }{\to }2\mathrm{KOH}+{\mathrm{I}}_2$
3) It oxidises sulphites to sulphates
${\mathrm{Na}}_2{\mathrm{SO}}_3+{\mathrm{H}}_2{\mathrm{O}}_2\stackrel{ }{\to }{\mathrm{Na}}_2{\mathrm{SO}}_4+{\mathrm{H}}_2\mathrm{O}$
4) It oxidises acidified ferrous sulphate to ferric sulphate
$2{\mathrm{FeSO}}_4+{\mathrm{H}}_2{\mathrm{SO}}_4+{\mathrm{H}}_2{\mathrm{O}}_2\stackrel{ }{\to } {\mathrm{Fe}}_2{\left({\mathrm{SO}}_4\right)}_3+2{\mathrm{H}}_2\mathrm{O}$
Reducing properties :
1) It reduces ozone to oxygen
${\mathrm{H}}_2{\mathrm{O}}_2+{\mathrm{O}}_3\stackrel{ }{\to }{\mathrm{H}}_2\mathrm{O}+2{\mathrm{O}}_2$
2) It reduces silver oxide to silver
${\mathrm{H}}_2{\mathrm{O}}_2+{\mathrm{Ag}}_2\mathrm{O}\stackrel{ }{\to }2\mathrm{Ag}+{\mathrm{H}}_2\mathrm{O}+{\mathrm{O}}_2$
3) It reduces lead dioxide to lead monoxide.
${\mathrm{PbO}}_2+{\mathrm{H}}_2{\mathrm{O}}_2\stackrel{ }{\to }\mathrm{PbO}+{\mathrm{H}}_2\mathrm{O}+{\mathrm{O}}_2$
4) It reduces chlorine to hydrogen chloride.
${\mathrm{Cl}}_2+{\mathrm{H}}_2{\mathrm{O}}_2\stackrel{ }{\to }2\mathrm{HCl}+{\mathrm{O}}_2$