In the balanced chemical equation $MnO_4^- + Br^- + H_2O \to MnO_2 + BrO_3^- + OH^-$,the coefficients of $MnO_4^-$,$BrO_3^-$,and $OH^-$ are respectively:

For the ionic reaction: $XBrO_3^{-} + YCr^{+3} + ZH_2O \rightarrow pBr_2 + qHCrO_4^{-} + rH^{+}$

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

In the following balanced reaction,
$X\,MnO_4^- + Y\,C_2O_4^{2-} + Z\,H^+ \rightleftharpoons X\,Mn^{2+} + 2Y\,CO_2 + \frac{Z}{2}\,H_2O$
values of $X, Y$ and $Z$ respectively are

In the following reaction $yMnO_4^- + xH^{+} + C_2O_4^{2-} \to yMn^{2+} + 2CO_2 + \frac{x}{2}H_2O$,the values of $x$ and $y$ are:

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 $Mn^{2+}$?