covalent bond

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Related to Molecular bonds: Chemical bonding, Covalent bonding

covalent bond

(kō'vā`lənt): see chemical bondchemical bond,
mechanism whereby atoms combine to form molecules. There is a chemical bond between two atoms or groups of atoms when the forces acting between them are strong enough to lead to the formation of an aggregate with sufficient stability to be regarded as an
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.

Covalent Bond

 

a chemical bond between two atoms that is formed by a shared electron pair (one electron from each atom). Covalent bonds exist both in molecules (in all states of aggregation) and between the atoms that form crystal lattices. They may unite like atoms (in H2 and C12 molecules and diamond crystals) or unlike atoms (in water molecules and crystals of carborundum, SiC).

Almost all the main bonds in the molecules of organic compounds are covalent (C—C, C—H, C—N, and so on). Covalent bonds are very strong, which explains the low chemical activity of paraffin hydrocarbons. Many inorganic compounds whose crystals have an atomic lattice (that is, are formed by a covalent bond) are refractory and characterized by great hardness and wear resistance; among them are certain carbides, suicides, borides, and nitrides (particularly borazone, BN), which are widely used in modern technology.

V. A. KIREEV

covalent bond

[kō′vā·lənt ′bänd]
(chemistry)
A bond in which each atom of a bound pair contributes one electron to form a pair of electrons. Also known as electron pair bond.
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