The oxidation states of $P$ in $PO_4^{3-}$,$S$ in $SO_4^{2-}$,and $Cr$ in $Cr_2O_7^{2-}$ are respectively:

In $Pb_3O_4$,the different oxidation states of $Pb$ are:

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

The oxidation number and the electronic configuration of sulphur in $H_2SO_4$ is

$A$ compound contains atoms of three elements $A$,$B$ and $C$. If the oxidation number of $A$ is $+2$,$B$ is $+5$ and that of $C$ is $-2$,the possible formula of the compound is:

In which among the following compounds,the oxidation number of nitrogen is $ +5 $?