molecole

Molecole are the smallest units of many chemical compounds that retain the properties of the compound as a whole. Typically, a molecule consists of two or more atoms held together by covalent bonds, which involve sharing electrons between atoms. In some contexts, ionic compounds form lattices rather than discrete molecules in the solid state, and their descriptions rely on formula units rather than individual molecules.

Molecular structure varies widely. Diatomic molecules such as hydrogen (H2), oxygen (O2), and nitrogen (N2) consist of two atoms, while larger molecules can contain hundreds or thousands of atoms arranged in specific geometries. The arrangement of atoms in a molecule gives rise to its geometry, polarity, and reactivity. Covalent bonds may be nonpolar or polar, and molecules also interact through hydrogen bonds, van der Waals forces, and other intermolecular interactions that influence physical properties like boiling points and solubility.

Isomers are molecules with the same chemical formula but different structures or spatial arrangements. Structural isomers differ in connectivity, while stereoisomers differ in three-dimensional orientation. These variations can lead to distinct chemical behaviors, biological activities, or scent and flavor profiles, even among compounds with identical formulas.

Molecole play central roles in chemistry, biology, medicine, and materials science. They range from simple gases and liquids to complex biomolecules such as proteins and nucleic acids. Analytical techniques like spectroscopy and X-ray crystallography, along with computational modeling, are used to determine their composition, structure, and properties.