How To Draw Resonance Structures Organic Chemistry

Resonance

In certain cases, molecules can be represent by more than ane reasonable Lewis construction that differ but in the location of π electrons.
Electrons in σ bonds accept a fixed location then they are said to be localised.
In contrast, π electrons that tin be drawn in different locations are said to be delocalised.
Collectively these Lewis diagrams are and then known as resonance structures or resonance contributors or resonance canonicals.
The "real" structure has characteristics of each of the contributors, and is oft represented as the resonance hybrid (call up of a hybrid breed which is a mixed brood). In a mode, the resonance hybrid is a mixture of the contributors.

( notation that a resonance hybrid cannot normally be written as an individual Lewis diagram ! ).

Yous should be able to draw all reasonable resonance structures for a given organic molecule. Examples.

The best way to "derive" resonance structures is by learning to "push button" curly arrows and starting from a reasonable Lewis structure.

Rules to recall for recognising resonance structures:

Atoms never move.
You tin can but move electrons in π bonds or lone pairs (that are in p orbitals)
The overall charge of the system must remain the same.
The bonding framework of a molecule must remain intact.