In which of the following molecules/ions BF3, NO2-, NH2- and H2O, the central atom is sp2 hybridised?
- NH2- and H2O
- NO2- and H2O
- BF3 and NO2-
- NO2- and NH2-
Answer
(3) BF3 and NO2-
Solution
Number of hybrid orbitals = σ bonds + lone pairs on the central atom.
BF3: 3 σ + 0 lp = 3 ⇒ sp2
NO2-: 2 σ + 1 lp = 3 ⇒ sp2
NH2-: 2 σ + 2 lp = 4 ⇒ sp3
H2O: 2 σ + 2 lp = 4 ⇒ sp3
∴ BF3 and NO2- are sp2 hybridised.
Answer: (3)