1. Basic Framework
- Phenol consists of a benzene ring (C₆H₆) in which one hydrogen atom is replaced by a hydroxyl group (–OH).
- So its molecular formula is C₆H₆O.
2. Bonding
- The benzene ring has six carbon atoms arranged in a hexagon with alternating single and double bonds (delocalized π-electrons).
- The –OH group is directly bonded to one of the carbon atoms of the benzene ring.
3. Resonance
- The lone pair of electrons on the oxygen atom of –OH interacts with the delocalized π-electrons of the benzene ring.
- This creates resonance structures, making the ring electron-rich especially at the ortho and para positions.
- This resonance explains why phenol is more reactive than benzene in electrophilic substitution reactions.
4. Geometry
- The benzene ring is planar.
- The oxygen atom in –OH is sp³ hybridized, and the O–H bond is polar, allowing hydrogen bonding.
In short: The structure of phenol is a benzene ring with an –OH group attached, stabilized by resonance between the oxygen lone pair and the aromatic π-system.