Resonance is due to

The number of possible resonance structures for $CO_3^{2-}$ is

The formal charge on the $O$ atom and the $P-O$ bond order in the $PO_4^{3-}$ ion are,respectively,.......

During the formation of the dimer $N_2O_4$ from two molecules of $NO_2$,the odd electron on the nitrogen atom of each $NO_2$ molecule pairs up. What is the resulting structure?

What is the $O-O$ bond length in the resonance hybrid of ozone (in $pm$)?

Explain the structure of $CO_{2}$ molecule.