molecuulconcept

The molecuulconcept is the central idea in chemistry that matter is composed of molecules, discrete assemblies of atoms bound together that act as the smallest unit of a substance retaining its chemical properties. A molecule is typically a neutral entity formed by covalent bonds between atoms; in some cases the term also covers ion-containing species in a specific arrangement, but a lattice of ions in a solid salt is usually not described as a single molecule.

Common examples include diatomic molecules such as H2 and O2, and polyatomic molecules such as H2O, CO2, and CH4. The identity of a molecule is described by its molecular formula, structural formula showing how atoms are connected, and three-dimensional geometry. The type and strength of bonds, as well as molecular symmetry, influence properties such as boiling and melting points, solubility, polarity, and reactivity. The concept also contrasts with extended networks like diamond or metallic lattices, where atoms extend in a repeating arrangement rather than forming discrete molecules.

The molecuulconcept underpins much of chemistry, including stoichiometry, molecular mass, and reaction mechanisms. It helps explain how substances combine, transform, and interact with energy. Historically, it emerged from Dalton’s atomic theory and Avogadro’s hypothesis, which linked atoms and molecules to measurable amounts of matter. Today, it remains a foundational paradigm for describing the composition and behavior of matter at the chemical level.