In the redox reaction
$x \ MnO + y \ PbO_2 + z \ HNO_3 \to a \ HMnO_4 + b \ Pb(NO_3)_2 + c \ H_2O$
Find the values of $x, y, z$.

In acidic medium,$K_2Cr_2O_7$ shows oxidising action as represented in the half reaction:
$Cr_2O_7^{2-} + XH^+ + Ye^- \rightarrow 2A + ZH_2O$
$X, Y, Z$ and $A$ are respectively:

In the given half-reaction $Cr_2O_7^{2-} + ZH^{+} + e^- \to Cr^{3+} + H_2O$,find the value of $Z$.

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 redox reaction
$MnO_{4}^{-} + C_{2}O_{4}^{2-} + H^{+} \longrightarrow Mn^{2+} + CO_{2} + H_{2}O$
the correct coefficients of the reactants for the balanced equation are
$MnO_{4}^{-} \quad C_{2}O_{4}^{2-} \quad H^{+}$

Number of moles of $KMnO_{4}$ reduced by $1 \ mol$ of $I^{-}$ in basic medium is