Lewis base

chemical compounds

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June 30, 2026

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A Lewis base is a chemical compound that can donate an unshared pair of electrons to another molecule in a chemical reaction. This definition, introduced by Gilbert N. Lewis, broadens the concept of bases beyond just proton acceptors. Lewis bases include substances like ammonia and its organic derivatives, as well as most negatively charged atoms or molecules (anions).12

In a Lewis acid-base reaction, the base provides the electron pair to form a new covalent bond with a Lewis acid, which is a species that can accept an electron pair. These reactions are fundamental in chemistry and can act as catalysts for various processes.23

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chromatography
Retention
…acids) to electron donors (Lewis bases). The interplay of these forces and temperature are reflected in the partition coefficient and determine the order on polarity and eluotropic strength scales. In the special case of ions, a strong electrostatic force exists in addition to the other forces; this electrostatic force…
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…acids) to electron donors (Lewis bases). The interplay of these forces and temperature are reflected in the partition coefficient and determine the order on polarity and eluotropic strength scales. In the special case of ions, a strong electrostatic force exists in addition to the other forces; this electrostatic force…
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chemical bonding
Theories of bonding in complexes
…pair, which is called a Lewis base, and a species that can accept an electron pair, which is called a Lewis acid. In complexes of the formula [M(H₂O)₆]ⁿ⁺, the central metal ion acts as the Lewis acid and the ligand molecules act as the Lewis bases by virtue of a…
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…pair, which is called a Lewis base, and a species that can accept an electron pair, which is called a Lewis acid. In complexes of the formula [M(H₂O)₆]ⁿ⁺, the central metal ion acts as the Lewis acid and the ligand molecules act as the Lewis bases by virtue of a…
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