Definition of resonance

[Seohyun Park 1L]

What exactly is the definition of resonance? Is it the fact that molecules can have multiple lewis structures or the fact that electrons are delocalized and there is a "blending of structures"?

[Sydney To 1D]

Resonance is the blending of structures; some lewis structures have multiple bonds in different locations and a resonance hybrid is a structure of the contributing Lewis structures.

[Rithana Srikanth 3L]

Resonance is a way of describing the electron distribution in molecules with more than one Lewis structure. The resonance hybrid is just a blending of different Lewis structures, such that the electrons are distributed equally across all the bonds instead of being in single/double bonds.

[Kevin ODonnell 2B]

We use resonance in order to show the different options for different bonding molecules. For example, in NO3 Nitrogen can form a double bond with oxygen on any of the 3 oxygen molecules. This gives us three different possibilities for which one Nitrogen can be bonding too. Since we do not know which one it is bonding with in the molecule we represent all the different possibilities through what we call resonance.

[haleyervin7]

When we draw all the resonant structures, is that just a model for how the bond is actually somewhere between a single and double, or are there actually that many different structures?

[Summer de Vera 2C]

When we draw all the resonant structures, is that just a model for how the bond is actually somewhere between a single and double, or are there actually that many different structures?

All the different resonance structures you draw are basically "one structure" that shows where and how the electrons are bonded in diff places. It essentially shows all the possibilities of where are how the electrons are bonded in a single structure.

[Katie_Duong_1D]

Resonance structures are a "blend" of all the different ways a certain molecule can bond together. Resonance structure have the same overall charge and composition, but the formal charges of each constituent atom may be different.

[Nathan Tran 4K]

Moreover, to add on to all of these answers, the "true" model for the bonds would be a blend of all the resonance structures, meaning that every bond between nitrogen and oxygen has characteristics of both a single bond and a double bond. Drawing multiple lewis structures of the same molecule to show different resonances is the way we express this idea.