Explain Lewis acid base theory with suitable example. Classify the following species into Lewis acids and Lewis bases and show how these act as Lewis acid/base.
a. `OH^(-)` b. `F^(-)` c. `H^(+)` d. `BCl_(3)`

Explanation

(a) Hydroxyl ion is a Lewis base it can donate an electron lone pair `(OH^(-))`.
(b) Fluoride ion acts as a Lewis base as it can donate any one of its electron lone pairs.
(c) A proton is a Lewis acid as it cane accept a lone pair of electrons from bases like hydroxyl ion and fluoride ion.
(d) `BCl_(2)` acts a Lewis acids as it can accept a lone pair of electrons from species like ammonia or amine molecules.