Is and isn’t resonance structure?

[Ari Summers 3H]

On Achieve last week there were molecules with both linear and circular bonds- just checking, these do not fall under resonance structure category, no?

[Maille Flynn 3H]

Yeah, they do not count as resonance structures because it was not simply a different rearrangement of double bonds, but rather a change in the whole structure. Resonance structures occur when the double bonds shift locations without changing the molecule. For the achieve question specifically, the ring versus linear structures would not be resonance structures.