When $KMnO_4$ is reduced with oxalic acid in acidic solution,the oxidation number of $Mn$ changes from

If $HNO_3$ changes into $N_2O$,the oxidation number of nitrogen is changed by

In the conversion $Br_2 \to BrO_3^-$,the oxidation state of bromine changes from

Oxidation numbers of $P$ in $PO_4^{3-}$,of $S$ in $SO_4^{2-}$ and that of $Cr$ in $Cr_2O_7^{2-}$ are respectively

What is the change in the oxidation state of nitrogen when $HNO_3$ is converted into $N_2O$?

In alkaline condition,$KMnO_4$ reacts as $2KMnO_4 + 2KOH \to 2K_2MnO_4 + H_2O + [O]$. The equivalent weight of $KMnO_4$ would be (Atomic mass of $K = 39$,$Mn = 55$,$O = 16$).