Chemistry - Redox Reactions Question with Solution | TestHub

How many of the following species give elemental sulfur on treating with ${\mathrm{H}}_2\mathrm{S}$?

$\mathrm{HN}{\mathrm{O}}_3$, ${\mathrm{O}}_3$, ${{\mathrm{H}}_2\mathrm{O}}_2$, $\mathrm{S}{\mathrm{O}}_2$, $\mathrm{F}{\mathrm{e}}^{3+}$ and $\mathrm{F}{\mathrm{e}}^{2+}$