lewis base: meaning, definition, pronunciation and examples
Low-frequency (Technical)Highly formal; specialized/technical/scientific (chemistry, biochemistry, materials science)
Quick answer
What does “lewis base” mean?
A chemical species that donates a pair of electrons to form a coordinate covalent bond with a Lewis acid.
Audio
Pronunciation
Definition
Meaning and Definition
A chemical species that donates a pair of electrons to form a coordinate covalent bond with a Lewis acid.
A substance with a region of high electron density (e.g., a lone pair, a pi bond) that acts as an electron-pair donor in chemical reactions, following the Lewis theory of acid-base interactions. This is a broader definition than the classical Brønsted-Lowry base, which is limited to proton acceptors.
Dialectal Variation
British vs American Usage
Differences
No significant lexical or definitional differences. Spelling of related terms follows regional conventions (e.g., Br: sulphur, aluminium; Am: sulfur, aluminum).
Connotations
Identical technical connotations in both varieties.
Frequency
Used exclusively within scientific contexts in both regions with equal frequency.
Grammar
How to Use “lewis base” in a Sentence
SUBJECT + acts as + a Lewis baseSUBJECT + is + a Lewis baseSUBJECT + donates + electron pairsLewis base + forms + a coordinate bondVocabulary
Collocations
Examples
Examples of “lewis base” in a Sentence
verb
British English
- The amine group can lewis-base to the metal centre.
- This molecule tends to act by lewis-basing the vacant orbital.
American English
- The amine group can Lewis-base to the metal center.
- This molecule tends to act by Lewis-basing the vacant orbital.
adjective
British English
- Its lewis-base character was crucial for catalysis.
- We studied the compound's lewis-base properties.
American English
- Its Lewis-base character was crucial for catalysis.
- We studied the compound's Lewis-base properties.
Usage
Meaning in Context
Business
Not used.
Academic
Used in chemistry, biochemistry, and materials science lectures, textbooks, and research papers to describe electron-donating species.
Everyday
Not used.
Technical
The primary domain of use. Found in chemical synthesis descriptions, catalysis, coordination chemistry, and discussions of reaction mechanisms.
Vocabulary
Synonyms of “lewis base”
Neutral
Weak
Vocabulary
Antonyms of “lewis base”
Watch out
Common Mistakes When Using “lewis base”
- Using 'Lewis base' interchangeably with 'base' in all chemical contexts (e.g., saying sodium hydroxide is a Lewis base; it's primarily a Brønsted-Lowry base).
- Confusing the role of a substance (e.g., water can act as both a Lewis acid and base, but is typically called a Lewis base in introductory contexts).
FAQ
Frequently Asked Questions
Generally, yes. A Brønsted-Lowry base (proton acceptor) must have a lone pair to bond with H⁺, which makes it an electron-pair donor (Lewis base). The Lewis definition is broader.
Absolutely. Many anions, like chloride (Cl⁻) or hydroxide (OH⁻), are excellent Lewis bases because they have high electron density and readily donate an electron pair.
They describe very similar concepts. 'Lewis base' is a broader term from acid-base theory, while 'nucleophile' is a kinetic term from organic chemistry describing a species attracted to a positive (electron-deficient) centre. Most nucleophiles are Lewis bases.
The definition was proposed by the American physical chemist Gilbert N. Lewis in 1923, expanding the concept of acids and bases beyond proton transfer.
A chemical species that donates a pair of electrons to form a coordinate covalent bond with a Lewis acid.
Lewis base is usually highly formal; specialized/technical/scientific (chemistry, biochemistry, materials science) in register.
Lewis base: in British English it is pronounced /ˈluːɪs ˈbeɪs/, and in American English it is pronounced /ˈluːɪs ˈbeɪs/. Tap the audio buttons above to hear it.
Learning
Memory Aids
Mnemonic
Think 'Lewis BASE' = 'BASically, it has spare ELECTRONS' to DONATE. Named for Gilbert N. Lewis.
Conceptual Metaphor
An electron-pair donor is a giver, a supplier of resources (electrons) to a needy receiver (the acid).
Practice
Quiz
Which of the following is the best description of a Lewis base?