Question

Assertion
In water, orthoboric acid behaves as a weak monobasic acid.

Reason
In water, orthoboric acid acts as a proton donor.

• A. Both assertion and reason are correct and reason is the correct explanation for assertion.
• B. Both assertion and reason are correct but reason is not the correct explanation for assertion.
• C. Assertion is correct but reason is incorrect.
• D. Both assertion and reason are incorrect.

Answer 1

The correct option is C Assertion is correct but reason is incorrect.

Though orthoboric acid $\left(H_{3}B{O}_3\right)$ contains three $OH$ bonds but cannot ionize in water to give a proton $\left(H^{+}\right).$ Due to vacant orbitals, it accepts lone pair of electrons and acts as a Lewis acid. By taking one $O{H}^{-}$, it forms $B(OH{)}_4^{-}$ Hence, option (c) is the answer.