The hybridization of nitrogen in primary amines is........, and the geometry of amines is ..........
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → sp3 and pyramidal
The nitrogen of an amine has three bond pairs and one lone pair; four electron pairs need four orbitals, so it is sp3 hybridised, and the lone pair makes the shape pyramidal.
Why the other options are incorrect
Option (1) dsp2 and planar — Incorrect. dsp2 needs a d orbital, which nitrogen (second period) does not have; it is found in square planar complexes such as \( \ce{[Ni(CN)4]^{2-}} \).
Option (2) dsp2 and pyramidal — Incorrect. The hybridisation is wrong for the same reason.
Option (3) sp3 and planar — Incorrect. The hybridisation is right, but a lone pair on an sp3 centre makes the shape pyramidal, not planar.
NCERT (2026-27 edition):
Structure of Amines
