Organic Chemistry

Resonance

Figure 14 Carbonate

In the Lewis structures above, carbonate (CO 3 ) has a resonance structure. Using lab-

oratory procedures to measure the bond length of each bond, we do not find that one

bond is shorter than the two others (remember, double bonds are shorter than single

bonds), but instead that all bonds are of the same length somewhere between the length

of typical double and single bonds.

10.2 Resonance Structures

Figure 15 Scheme 1. Resonance structures
of Benzene

Resonance structuresare diagrammatic tools used predominately in organic chemistry^1
to symbolizeresonant bondsbetween atom^2 s in molecule^3 s. The electron density of these
bonds is spread over the molecule, also known as the delocalization^4 of electron^5 s. Reso-
nance contributors for the same molecule all have the same chemical formula^6 and same
sigma framework, but the pi electrons will be distributed differently among the atoms. Be-

1 https://en.wikipedia.org/wiki/organic%20chemistry
2 https://en.wikipedia.org/wiki/atom
3 https://en.wikipedia.org/wiki/molecule
4 https://en.wikipedia.org/wiki/delocalization
5 https://en.wikipedia.org/wiki/electron
6 https://en.wikipedia.org/wiki/chemical%20formula