In alkaline medium,the reaction of hydrogen peroxide with potassium permanganate produces a compound in which the oxidation state of $Mn$ is $....$

The heating of $(NH_4)_2Cr_2O_7$ produces another chromium compound along with $N_2$ gas. The change of the oxidation state of $Cr$ in the reaction is

In neutral or faintly alkaline solution,$8$ moles of permanganate anion quantitatively oxidize thiosulphate anions to produce $X$ moles of a sulphur containing product. The magnitude of $X$ is

When $4$ moles of electrons are added to $NO_3^-$,the product obtained is .......

In the titration of $KMnO_{4}$ and oxalic acid in acidic medium,the change in oxidation number of carbon at the end point is

In the balanced chemical reaction,$IO_3^- + a\;I^{-} + b\;H^{+} \to c\;H_2O + d\;I_2$,$a$,$b$,$c$,and $d$ respectively correspond to