p-Block Elements-I 1 Question 9

9. $\mathrm{H} _{3} \mathrm{BO} _{3}$ is

$(2003,1 \mathrm{M})$

(a) monobasic acid and weak Lewis acid

(b) monobasic and weak Bronsted acid

(c) monobasic and strong Lewis acid

(d) tribasic and weak Bronsted acid

Show Answer

Answer:

Correct Answer: 9. (a)

Solution:

  1. Orthoboric acid is a weak, monobasic, Lewis acid.

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$p \pi-p \pi$ backbonding between ’ $\mathrm{B}$ ’ and ’ $\mathrm{O}$ ’ decreases acid strength greatly :

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