Definition

1. Noun:
   • A chemical bond formed between atoms by the sharing of one or more pairs of electrons: This is the primary scientific meaning. It describes a strong, stable connection where atoms share their outer electrons to achieve a full electron shell, resulting in the formation of a molecule.

Usage and Examples

• Noun:
  • A water molecule is held together by strong covalent bonds between the oxygen and hydrogen atoms.
  • In organic chemistry, the carbon-carbon covalent bond is fundamental to the structure of countless compounds.
  • The strength of a covalent bond depends on factors like the size of the atoms and the number of shared electron pairs.

Advanced Usage

• Coordinate (dative) covalent bond: A specific type of covalent bond where both shared electrons are donated by the same atom.
  • In the ammonium ion (NH₄⁺), one of the bonds is a coordinate covalent bond where nitrogen donates both electrons to hydrogen.
• Polar vs. Nonpolar covalent bond: Describes the nature of the electron sharing. In a polar bond, electrons are shared unequally due to differences in electronegativity.
  • The bond in a hydrogen chloride (HCl) molecule is a polar covalent bond.

Variants and Related Words

• Covalently (adverb): In a manner involving a covalent bond.
  • The atoms are covalently bonded.
• Covalency / Covalence (noun): The number of electron pairs an atom can share with others; the state of being covalently bonded.
• Covalent compound (noun phrase): A compound whose atoms are held together by covalent bonds.
  • Sugar is a covalent compound.

Synonyms

• Electron-pair bond: A more descriptive synonym emphasizing the shared electron pair.
• Molecular bond: A term sometimes used, though it can be less precise as it may also refer to intermolecular forces.

Related Phrases and Concepts

• Single/Double/Triple bond: Refers to covalent bonds involving one, two, or three shared pairs of electrons, respectively.
  • Oxygen gas (O₂) contains a double covalent bond.
• Bond energy: The amount of energy required to break a covalent bond.
• Bond length: The average distance between the nuclei of two bonded atoms in a covalent bond.

Noun

1. a chemical bond that involves sharing a pair of electrons between atoms in a molecule