Question

Question: The N atom in${\mathbf{CH}}_{\mathbf{3}}{\mathbf{CONH}}_{\mathbf{2}}$ (acetamide) is ${\mathbf{sp}}^{\mathbf{2}}$ hybridized, even though it is surrounded by four groups. Using this information, draw a diagram that shows the orbitals used by the atoms in the $\mathbf{-}{\mathbf{CONH}}_{\mathbf{2}}$ portion of acetamide, and offer an explanation as to the observed hybridization

Short answer

Answer

Step-by-step solution

Step-by-Step Solution Step 1: Resonance structures

The combination of one or more structures used to portray the chemical bonding in molecules is known as the resonance structure.

The resonance structures of acetamide

Resonance structures of acetamide

The nitrogen is${\mathrm{sp}}^2$ hybridized because it is involved in resonance with the carbonyl group.

The unhybridized p orbitals on nitrogen, carbon, and oxygen overlap laterally, and the lone pair on the nitrogen atom is delocalized on these three atoms.

Orbital diagram representing the bonding in  -CONH2

The unhybridized p orbitals on nitrogen, carbon, and oxygen overlap laterally, and the lone pair on the nitrogen atom is delocalized on these three atoms.

Orbitals involved in bonding $-{\mathrm{CONH}}_2$

To attain additional stability by virtue of resonance, delocalization of electrons is compulsory, which is possible only if nitrogen is ${\mathrm{sp}}^2$ hybridized.