Question

Among the following which is correct?

• A. Cyclopentadienyl anion is antiaromatic whereas benzene is aromatic.
• B. Benzene is aromatic whereas cyclopentadienyl is nonaromatic.
• C. Both cyclopentadienyl anion and benzene are aromatic.
• D. None of these

Answer 1

The correct option is C Both cyclopentadienyl anion and benzene are aromatic.


Both are planar .
In cyclopentadienyl anion, the negative charge is in delocalisation with the ring double bonds.
Both have $6\pi e^{-}$, i.e. $(4n+2)\pi e^{-}$ thus following huckel's rule.
Both cyclopentadienyl anion and benzene are aromatic