When acetamide, CH3CONH2, is protonated in strong acid, the proton adds mainly to

the carbonyl oxygen, because the resulting cation is stabilised by resonance with nitrogen

the nitrogen, because it has a lone pair

the carbonyl oxygen, because the resulting cation is stabilised by resonance with nitrogen

the nitrogen, because oxygen is more electronegative

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When acetamide, $CH X_{3} CONH X_{2}$ , is protonated in strong acid, the proton adds mainly to

Athe nitrogen, because it has a lone pair
Bthe methyl carbon
Cthe carbonyl oxygen, because the resulting cation is stabilised by resonance with nitrogen
Dthe nitrogen, because oxygen is more electronegative

Answer: C

Protonation at O gives

CH X_{3} C (OH) = NH X_{2} X^{+}

, a resonance-stabilised cation in which the positive charge is shared by O and N. Protonation at N would leave the N lone pair unavailable for conjugation and the cation would be unstabilised, so O-protonation is favoured.

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When acetamide, CHX3​CONHX2​, is protonated in strong acid, the proton adds mainly to

Answer: C

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When acetamide, $CH X_{3} CONH X_{2}$ , is protonated in strong acid, the proton adds mainly to