Which of the following compounds contains chlorine in $+5$ oxidation state?

Oxidation number of $Mn$ in $K_2MnO_4$ and $MnSO_4$ are respectively

In chromite ore,the oxidation number of iron and chromium are respectively

Assign oxidation number to the underlined elements in each of the following species:
$(a)$ $NaH_2\underline{P}O_4$
$(b)$ $NaH\underline{S}O_4$
$(c)$ $H_4\underline{P_2}O_7$
$(d)$ $K_2\underline{Mn}O_4$
$(e)$ $Ca\underline{O_2}$
$(f)$ $Na\underline{B}H_4$
$(g)$ $H_2\underline{S_2}O_7$
$(h)$ $KAl(\underline{S}O_4)_2 \cdot 12H_2O$

The oxidation numbers of the two $Cl$ atoms in bleaching powder,$CaOCl_2$,are

Which of the following is $NOT$ correct for $C_3O_2$?