Chemistry - GOC Question with Solution | TestHub

The $\mathrm{C}=\mathrm{O}$ bond is polarised (${\mathrm{C}}^{+}-{\mathrm{O}}^{-}$), so the ring has 3 $\mathrm{C}=\mathrm{C}$ (6π) with an empty p orbital : the tropylium oxide form, 6π = 4n+2 (n = 1). Aromatic.