lone pair: meaning, definition, pronunciation and examples
Low (exclusively in technical/scientific contexts)Technical/Academic (specialized scientific terminology)
Quick answer
What does “lone pair” mean?
In chemistry, a pair of valence electrons that are not shared with another atom and are not involved in bonding.
Audio
Pronunciation
Definition
Meaning and Definition
In chemistry, a pair of valence electrons that are not shared with another atom and are not involved in bonding.
A pair of electrons in the valence shell of an atom that are not used in covalent bonding, often responsible for the shape of molecules and their ability to act as Lewis bases.
Dialectal Variation
British vs American Usage
Differences
No significant lexical or semantic differences. Pronunciation of 'pair' may differ slightly (/peə/ vs /pɛr/). Spelling and usage are identical.
Connotations
Identical technical connotations in both varieties.
Frequency
Frequency is equally low and confined to chemistry/related fields in both regions.
Grammar
How to Use “lone pair” in a Sentence
The atom has a lone pair.A lone pair is present on the nitrogen.The lone pair occupies an sp3 orbital.Molecules with lone pairs...Vocabulary
Collocations
Usage
Meaning in Context
Business
Not used.
Academic
Used exclusively in chemistry, physics, and materials science textbooks, lectures, and research papers to describe molecular structure and reactivity.
Everyday
Not used in everyday conversation.
Technical
Core terminology in chemistry for discussing VSEPR theory, molecular geometry, Lewis structures, and coordination chemistry.
Vocabulary
Synonyms of “lone pair”
Neutral
Weak
Vocabulary
Antonyms of “lone pair”
Watch out
Common Mistakes When Using “lone pair”
- Using 'lone pair' to refer to a single electron (it is always a PAIR).
- Confusing 'lone pair' with 'free radical'.
- Attempting to use the term in non-scientific contexts.
FAQ
Frequently Asked Questions
No, they are completely different. A lone pair is two electrons paired together in an orbital. An unpaired electron is a single electron in an orbital by itself.
Yes. A lone pair can be donated to form a coordinate (dative) covalent bond with a Lewis acid, which is a key concept in coordination chemistry and catalysis.
No. Only atoms with valence electrons that are not involved in bonding have lone pairs. For example, the carbon atoms in methane (CH4) have no lone pairs, while the oxygen in water has two.
Lone pairs are crucial for predicting molecular shape (via VSEPR theory), understanding chemical reactivity (especially in bases and nucleophiles), and explaining the properties of many materials and biological molecules.
In chemistry, a pair of valence electrons that are not shared with another atom and are not involved in bonding.
Lone pair is usually technical/academic (specialized scientific terminology) in register.
Lone pair: in British English it is pronounced /ˌləʊn ˈpeə/, and in American English it is pronounced /ˌloʊn ˈpɛr/. Tap the audio buttons above to hear it.
Learning
Memory Aids
Mnemonic
Imagine a person (atom) with two hands (electrons) in their pockets, not shaking hands (bonding) with anyone – that's a LONE PAIR.
Conceptual Metaphor
Often conceptualized as a 'cloud' of negative charge or a region of space that can 'donate' or 'push' other electron pairs away (steric repulsion).
Practice
Quiz
What is the primary role of a lone pair in a Lewis acid-base reaction?