Equivalent weight of $H_3PO_2$ when it disproportionates into $PH_3$ and $H_3PO_3$ is

Which one of the following does not undergo disproportionation reaction?

Which species among the following does not show disproportionation reactions?

In the following reaction,assign the oxidation state for the underlined atom in the product of complete hydrolysis at $R.T.$:
$\underline{Cl}O_3 + H_2O \longrightarrow HClO_3 + HClO_4$

From the given reactions, identify the disproportionation reaction:
$(i) \ Cl_{2(g)} + 2KI_{(aq)} \longrightarrow 2KCl_{(aq)} + I_{2(s)}$
$(ii) \ Cl_{2(g)} + 2OH^{-}_{(aq)} \longrightarrow ClO^{-}_{(aq)} + Cl^{-}_{(aq)} + H_2O_{(l)}$
$(iii) \ Mg_{(s)} + 2HCl_{(aq)} \longrightarrow MgCl_{2(aq)} + H_{2(g)}$
$(iv) \ 2H_2O_{2(aq)} \longrightarrow 2H_2O_{(l)} + O_{2(g)}$

The disproportionation products of $ortho-phosphorous$ acid are