Question

$B(OH)_3$ is a

• A. Lewis acid
• B. Lewis base
• C. Bronsted base
• D. Bronsted acid

Answer 1

Answer: (A)

Lewis acid

Answer 2

Lewis acids are the electron-pair acceptor and bases are the electron-pair donor. Bronsted acids give proton whereas bases accept proton. Boric acid or orthoboric acid $\left( H _{3} BO _{3}\right.$ or $\left. B ( OH )_{3}\right)$ can accept a pair of electrons from Lewis bases and hence, act as Lewis acid.