NTA Abhyas NEET2020ChemistryIonic EquilibriumPractice
Among the following, which is the strongest Lewis acid?
Options
- AB F 3
- BB C l 3
- CB B r 3
- DB I 3
Correct answer
D. B I 3
Step-by-step solution
The strengths of boron halides as Lewis acids are in the order BI 3 > BBr 3 > BCl 3 > BF 3 . This order is the opposite of what is expected on steric grounds as well as from considerations of electronegatively. It can be explained in terms of boron-halogen-bonding. Here, acidic nature ∝ 1 e x t e n t o f b a c k b o n d i n g