Phenol is acidic, basic, or neutral?

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Multiple Choice

Phenol is acidic, basic, or neutral?

Explanation:
Phenol behaves as an acid because the hydrogen on its hydroxyl group can be donated, forming the phenoxide ion. The key is that the negative charge on the oxygen, once deprotonated, is stabilized by resonance with the aromatic ring. This delocalization spreads the charge over the ortho and para positions, lowering the energy of the conjugate base and making deprotonation favorable in water. That stabilization explains why phenol, while a weak acid, does donate a proton (pKa around 10), unlike a substance that would act as a base or remain neutral. It isn’t behaving as a base in ordinary conditions, and it isn’t amphoteric, since it doesn’t reliably act as both an acid and a base. So phenol is acidic.

Phenol behaves as an acid because the hydrogen on its hydroxyl group can be donated, forming the phenoxide ion. The key is that the negative charge on the oxygen, once deprotonated, is stabilized by resonance with the aromatic ring. This delocalization spreads the charge over the ortho and para positions, lowering the energy of the conjugate base and making deprotonation favorable in water. That stabilization explains why phenol, while a weak acid, does donate a proton (pKa around 10), unlike a substance that would act as a base or remain neutral. It isn’t behaving as a base in ordinary conditions, and it isn’t amphoteric, since it doesn’t reliably act as both an acid and a base. So phenol is acidic.

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