Lewis acid

American

noun

Chemistry.

any substance capable of forming a covalent bond with a base by accepting a pair of electrons from it.

Lewis acid British

noun

a substance capable of accepting a pair of electrons from a base to form a covalent bond Compare Lewis base

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of Lewis acid

First recorded in 1940–45; named after G. N. Lewis

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

They found that adding a key ingredient could help: a chemical known as a Lewis acid added to the liquid solution redirected those molecules.

From Science Daily • Jan. 2, 2024

In addition, transition metals form a wide variety of stable coordination compounds, in which the central metal atom or ion acts as a Lewis acid and accepts one or more pairs of electrons.

From Textbooks • Feb. 14, 2019

Being short of the preferred octet, BF3 is a very good Lewis acid and reacts with many Lewis bases; a fluoride ion is the Lewis base in this reaction, donating one of its lone pairs:

From Textbooks • Feb. 14, 2019

The important aspect of complex ions for this chapter is that they form by a Lewis acid-base reaction with the metal being the Lewis acid.

From Textbooks • Feb. 14, 2019

Many Lewis acid-base reactions are displacement reactions in which one Lewis base displaces another Lewis base from an acid-base adduct, or in which one Lewis acid displaces another Lewis acid:

From Textbooks • Feb. 14, 2019

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023