Final answer:
The hybridization of the central atom (N) in a molecule can be determined by counting the regions of electron density around it, with sp² for three regions as in NO₂, and sp³ for four regions as in NH₃. So the correct answer is Option B.
Step-by-step explanation:
The hybridization of the central atom (N) in the molecule N3 is sp².
In the molecule N3, the central nitrogen atom is bonded to three other nitrogen atoms. Each of these bonds is formed by the overlap of a 2p orbital on the central nitrogen atom and a 2p orbital on the bonded nitrogen atom, resulting in a trigonal planar geometry.
This trigonal planar geometry is characteristic of sp² hybridization, where the central atom has three sigma bonds and no lone pairs of electrons.