In alkaline medium,the reduction of permanganate anion involves a gain of $........$ electrons.

Assign $A, B, C, D$ from the given type of reaction.
$CuSO_4 + 2KCN \longrightarrow CuCN \downarrow + (CN)_2 \uparrow + K_2SO_4$

For the redox reaction $MnO_4^- + C_2O_4^{2-} + H^+ \longrightarrow Mn^{2+} + CO_2 + H_2O$,the correct coefficients of the reactants for the balanced equation are $MnO_4^-$ - $C_2O_4^{2-}$ - $H^+$

The reaction of white phosphorus on boiling with alkali in an inert atmosphere results in the formation of product '$A$'. The reaction of $1 \ mol$ of '$A$' with an excess of $AgNO_3$ in an aqueous medium gives ............... $mol(s)$ of $Ag$. (Round off to the Nearest Integer).

$6 \times 10^{-3}$ mole $K_2Cr_2O_7$ reacts completely with $9 \times 10^{-3}$ mole $X^{n+}$ to give $XO_3^-$ and $Cr^{3+}$. The value of $n$ is

For the decolourization of $1 \ mole$ of $KMnO_4$,the moles of $H_2O_2$ required is: (in $.5$)