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Question
Give a plausible explanation for the following:
Why are amines less acidic than alcohols of comparable molecular masses?
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Solution
Loss of a proton from an amine gives an amide ion, while loss of a proton from alcohol gives an alkoxide ion.
\[\ce{R-NH2 -> R-NH– + H+}\]
\[\ce{R-O-H -> R-O^- + H+}\]
Since O is more electronegative than N, it will attract positive species more strongly in comparison to N. Thus, RO− is more stable than RNH−. Thus, alcohols are more acidic than amines. Conversely, amines are less acidic than alcohols.
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