BF3 is planar and electron deficient compound. Hybridization and number of electrons around the central atom, respectively are :
- sp2 and 8
- sp3 and 4
- sp3 and 6
- sp2 and 6
Answer
(4) sp2 and 6
Solution
B (Z = 5): 1s2 2s2 2p1; in the excited state 2s1 2px1 2py1.
⇒ One 2s and two 2p orbitals hybridise → three sp2 orbitals, which form three B–F bonds (trigonal planar).
⇒ Electrons around B = 3 bond pairs = 6 electrons (incomplete octet, so BF3 is electron deficient).
∴ sp2 and 6
Answer: (4)