Resonance structures [ENDORSED]

[Khachik_Hmayakyan_2E]

When forming resonance structures, can one resonance structure be a double bond with an oxygen atom and the other resonance structure be a double bond with a nitrogen atom? Or must the resonance structure be with the same elemental species within the molecule?

[Mikaela Gareeb 3G]

It's possible to have resonance structures in which the resonance occurs with different elements so long as, in this case, nitrogen and oxygen do not have expanded octets. Also, be aware of the formal charge; if the compound is neutral and double bonding the nitrogen or oxygen gives you an overall negative or positive charge, then it is not a resonance structure.

[Emma Cole 3F]

I am a little confused on the concept of resonance. Is it just that the same molecule has different possible structures?

[Beata_Vayngortin_3L]

yes, if a molecule has resonance that means it can be drawn in multiple ways. resonance structures have the same atoms involved but they differ by the use and location of bonds and lone pairs. resonance structures can be used to figure out the best visual representation of an atom (based on formal charges,) but we know that none of the resonance structures we draw are actually accurate because the real life structure is a blend of all the resonance structures. another thing about resonance is that it tells us the molecule is more stable because the electrons are delocalized.