Question

The correct statement(s) for orthoboric acid is/are

• A. It behaves as a weak acid in water due to self ionization.
• B. Acidity of its aqueous solution increases upon addition of ethylene glycol.
• C. It has a three dimensional structure due to hydrogen bonding.
• D. It is a weak electrolyte in water.

Answer 1

Answer: (B), (D)

(A) $H _{3} BO _{3}$ is a weak monobasic Lewis acid.
$H _{3} BO _{3}+ H - OH \rightleftharpoons B ( OH )_{4}^{-}+ H ^{+}\dots$(i)
(B) Equilibrium (i) is shifted in forward direction by the addition of syn-diols like ethylene glycol which forms a stable complex with $B ( OH )_{4}^{-}$

(C) It has a planar sheet like structure due to hydrogen bonding.
(D) $H_3BO_3$ is a weak electrolyte in water.