Question

Among the halides
$(1)BCl_{3} $
$(2) AlCl_{3}$
$(3) GaCl_{3}$
$ (4) InCl_{3}$
The order of decreasing Lewis acid character is:

• A. $1,2, 3,4$
• B. $2, 3,4,1$
• C. $3,4, 2, 1$
• D. $4, 3, 2, 1$

Answer 1

Answer: (D)

The acidic character of chlorides increases down the group $BCl_{3}$ is weak acid to show $p\pi - p\pi$ back bonding.