Covalent bonds

Science

Definition

Covalent bonds form when two atoms share one or more pairs of electrons to achieve stable electron configurations. They typically occur between nonmetal atoms and can be single, double, or triple bonds depending on the number of shared electron pairs.

Examples

  • Water (H₂O) has two covalent bonds, each sharing one electron pair between oxygen and hydrogen
  • Oxygen gas (O₂) has a double covalent bond, sharing two electron pairs
  • Nitrogen gas (N₂) has a triple covalent bond, making it very stable and unreactive
Key Fact

Nonpolar covalent bonds share electrons equally; polar covalent bonds share unequally due to electronegativity differences.

Related Terms

Ionic bonds Lewis structures Electronegativity Vsepr

Study This Concept

Practice covalent bonds with free review games in these units:

AP Chemistry Unit 2: Molecular and Ionic Bonding Chemistry Unit 3: Chemical Bonding