Why is phenol significantly more acidic than cyclohexanol (pKa ~ 10 vs ~ 16)?
Answer and explanation
Correct answer: A. The phenoxide conjugate base is stabilized by resonance delocalization into the aromatic ring
Deprotonation of phenol yields phenoxide, where the negative charge on oxygen is delocalized over the ortho and para positions of the aromatic ring through resonance. In cyclohexanol, negative charge remains localized on oxygen without resonance.
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