Resonance is a phenomenon that happens when a molecule can exist in a number of Lewis constructions that differ solely within the placement of electrons. A resonance hybrid is a illustration of the molecule that could be a weighted common of the entire doable Lewis constructions. To attract a resonance hybrid, you first want to attract the entire doable Lewis constructions for the molecule. Then, you want to decide the relative contribution of every Lewis construction to the resonance hybrid. The relative contribution of a Lewis construction is decided by its vitality. The decrease the vitality of a Lewis construction, the higher its contribution to the resonance hybrid.
Resonance is a crucial idea in chemistry as a result of it might probably assist to clarify a wide range of molecular properties, comparable to bond lengths and bond angles. For instance, the benzene molecule is a resonance hybrid of two Kekule constructions. The 2 Kekule constructions have totally different bond lengths and bond angles, however the resonance hybrid has a mean bond size and bond angle that’s intermediate between the 2 Kekule constructions.