Question

Explain the important aspects of resonance with reference to the $CO_3^{2-}$ ion.

Answer 1

According to experimental findings, all carbon to oxygen bonds in $CO_3^{2-}$ are equivalent. Hence, it is inadequate to represent $CO_3^{2-}$ ion by a single Lewis structure having two single bonds and one double bond.

Therefore, carbonate ion is described as a resonance hybrid of the following structures: