Q. Which of the following is least likely to behave as Lewis base?
A) OH⁻
B) H₂O
C) NH₃
D) BF₃
Explanation
[Solution from source] A Lewis base donates an electron pair. OH⁻, H₂O and NH₃ all have lone pairs, whereas BF₃ has an incomplete octet on boron and accepts a pair, so it is a Lewis acid and least likely to act as a base. Answer (4).
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.