$1$ mole of $PbS$ is oxidised by "$X$" moles of $O_3$ to get "$Y$" moles of $O_2$. $X + Y = $ . . . . . . .

Manganese ions $(Mn^{2+})$ can be oxidised by persulphate ions $(S_2O_8^{2-})$ according to the following half-equations:
$S_2O_8^{2-} + 2e^- \longrightarrow 2SO_4^{2-}$
$Mn^{2+} + 4H_2O \longrightarrow MnO_4^- + 8H^+ + 5e^-$
How many moles of $S_2O_8^{2-}$ are required to oxidise $1 \ mole$ of $Mn^{2+}$?

Equivalent mass of the oxidizing agent in the reaction $SO_2 + 2H_2S \to 3S + 2H_2O$ is

When chlorine gas is passed through an aqueous solution of $KBr$,the solution turns orange brown due to the formation of

Which of the following reactions of $KMnO_4$ occurs in acidic medium?

In balancing the half-reaction $S_2O_3^{2-} \to S_{(s)}$,the number of electrons that must be added is: