It is known that benzene has two main resonance forms
Often we still draw benzene molecule as one of them
My question is, actually when we draw the lower figure, do we refer to the whole benzene molecule or one of the resonance structure or depend on the context?
Answer
I approach this question from the opposite direction.
Benzene is commonly drawn as a ‘cyclohexatriene’ corresponding to the Kekulé structure, i.e. with three single bonds and three double bonds, despite the fact that the six bonds of benzene are actually indistinguishable from each other.

This graphical representation of benzene is in accordance with Nomenclature of Organic Chemistry – IUPAC Recommendations and Preferred Names 2013 (Blue Book) as well as Graphical Representation Standards for Chemical Structure Diagrams (IUPAC Recommendations 2008).
Therefore, when you see such a structure diagram in the literature, it usually represents a real benzene ring and not a particular resonance form.
However, if a structure diagram is explicitly meant to show the individual resonance forms, they are commonly drawn with a two-sided arrow.



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