The resonance energy of the following heterocycles is in the order:

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

With respect to resonance structures of $CO_3^{2-}$ ion, which of the following statements are correct?
$(a)$ All $C – O$ bonds in $CO_3^{2-}$ are equivalent
$(b)$ There are three resonance structures possible for $CO_3^{2-}$ ion
$(c)$ The position of carbon and oxygen should change in every resonance structure
$(d)$ The formal charge on carbon atom is $0$

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

Draw the possible resonance structures for $CH_3 - \ddot{O} - CH_2^+$ and predict which of the structures is more stable. Give reason for your answer.

Consider the following molecules/species: tropone $(x)$, acetone $(y)$, acetate ion $(z)$. The correct order of carbon-oxygen bond length is: