For the redox reaction $xP_4 + yHNO_3 \to H_3PO_4 + NO_2 + H_2O$,find the values of $x$ and $y$.

Observe the following stoichiometric equation:
$P_4 + 3 OH^{-} + 3 H_2 O \rightarrow PH_3 + 3 X^{-}$
What is the conjugate acid of $X^{-}$?

In the reaction of oxalate with permanganate in acidic medium,the number of electrons involved in producing one molecule of $CO_2$ is

$ClO_2$ oxidizes $H_2O_2$ to $O_2$ in basic medium and is itself reduced to $Cl^-$. How many moles of $H_2O_2$ will be oxidized by one mole of $ClO_2$ (in $.5$)?

Chlorine undergoes disproportionation in alkaline medium as shown below:
$a Cl_{2(g)} + b OH^{-}_{(aq)} \rightarrow c ClO^{-}_{(aq)} + d Cl^{-}_{(aq)} + e H_2O_{(l)}$
The values of $a, b, c$ and $d$ in a balanced redox reaction are respectively:

The dark purple colour of $KMnO_4$ disappears in the titration with oxalic acid in acidic medium. The overall change in the oxidation number of manganese in the reaction is.