lewis acid: meaning, definition, pronunciation and examples

According to the broadest Lewis definition, yes, because a Brønsted acid's proton can accept an electron pair. However, in practical discussion, 'Lewis acid' often refers specifically to non-protonic electron-pair acceptors like BF₃ or metal ions.

A Brønsted acid is specifically defined as a proton (H⁺) donor. A Lewis acid is defined as an electron-pair acceptor. All Brønsted acids are Lewis acids, but not all Lewis acids are Brønsted acids (e.g., BF₃).

Yes, molecules that have both electron-deficient sites and lone pairs can act as either, depending on the reaction partner. Water is a classic example: it acts as a Lewis base when it donates a lone pair to a metal ion, and as a Lewis acid when its hydrogen atom accepts a lone pair (in Brønsted acidity).

It provides a unifying theory of acid-base reactions that applies far beyond aqueous solutions, explaining behaviour in organic reactions, coordination chemistry, catalysis, and solid-state chemistry where proton transfer is not involved.

A chemical species that accepts a pair of electrons to form a coordinate covalent bond.

Lewis acid is usually formal; academic; technical (chemistry) in register.

Lewis acid: in British English it is pronounced /ˈluː.ɪs ˈæs.ɪd/, and in American English it is pronounced /ˈluː.ɪs ˈæs.ɪd/. Tap the audio buttons above to hear it.