Which structures are aromatic? Make your call based on the electron distributions shown here, not on possible resonance structures.

Question

Quizplus · Accepted Answer

Structures I and III both have a continuous ring of pi electrons, which satisfies the criteria for aromaticity. Structure II has a non-aromatic ring of 10 pi electrons, while structure IV has two separate aromatic rings, but they are not conjugated with each other, and therefore do not meet the criteria for aromaticity.

Which Structures Are Aromatic? Make Your Call Based on the Electron