Question

An aqueous solution of boric acid is found to be weakly acidic in nature. This acidic character arises due to the following reasons.

• A. It is a protic acid which donates protons in aqueous solution.
• B. It is a Lewis acid which abstracts $O{H}^{-}$ from water and leaves $H^{+}$ to make the solution acidic.
• C. It gives metaboric acid when dissolves in water
• D. It is prepared by reaction of borax with sulphuric acid hence it behaves as an acid.

Answer 1

Answer: (B)

It is a Lewis acid which abstracts $O{H}^{-}$ from water and leaves $H^{+}$ to make the solution acidic.

Boric acid, when reacts with water, abstracts ${OH}^{-}$ ions and releases ${H_{3}O}^{+}$ ions.

$H_{3}B{O}_3+H_{2}O⟶{H_{3}O}^{+}+{H_{2}B{O}_3}^{-}$

This property of boric acid makes it acidic.