Question

Which of the following is the strongest Lewis acid.

• A. $BI_{3}$
• B. $BBr_{3}$
• C. $BCl_{3}$
• D. $BF_{3}$

Answer 1

Answer: (A)

$BI_{3}$

Answer 2

Larger the size of halogen atom less is the back donation of electrons into empty 2p orbital of B.