lone pair

British

noun

chem a pair of valency electrons of opposite spin that are not shared between the atoms in a molecule and are responsible for the formation of coordinate bonds

"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

Example Sentences

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The nitrogen atom is sp3 hybridized with one hybrid orbital occupied by the lone pair.

From Textbooks • Feb. 14, 2019

Phosphorus and nitrogen can form sp3 hybrids to form three bonds and hold one lone pair in PF3 and NF3, respectively.

From Textbooks • Feb. 14, 2019

For example, the nitrogen atom in ammonia is surrounded by three bonding pairs and a lone pair of electrons directed to the four corners of a tetrahedron.

From Textbooks • Feb. 14, 2019

For example, NH3 reacts with BF3 because the lone pair on nitrogen can be shared with the boron atom:

From Textbooks • Feb. 14, 2019

Two electrons remain, and this lone pair is placed on the Xe atom:

From Textbooks • Feb. 14, 2019

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