Explain the important aspects of resonance with reference to the CO2−3 ion.
The pi bond electrons are delocalised to transfer from one to another to make different structure. According to experimental findings, all carbon to oxygen bonds in CO2−3 are equivalent.
Hence, it is inadequate to represent CO2−3 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: