gasteilchen

Gasteilchen is a term that may be found in some German-language texts to denote the individual constituents of a gas. The standard spelling in German is usually Gasteilchen (two words) or Gas-Teilchen; Gasteilchen as a single word is uncommon and can reflect stylistic variation or misspelling. In physics, the concept refers to atoms or molecules that make up a gaseous phase.

Gasteilchen are characterized by high mobility and rapid, largely random motion. In dilute gases they interact mainly through short-range, elastic collisions with other particles and with container walls. These collisions transfer momentum and energy but, in idealized models, interparticle forces apart from these collisions are neglected. The collective behavior of vast numbers of gasteilchen gives rise to observable macroscopic properties such as pressure, volume, and temperature.

In the kinetic theory of gases, the properties of gasteilchen are described statistically. The Maxwell–Boltzmann distribution describes the spread of speeds among the particles at a given temperature, and the equipartition theorem relates translational and internal degrees of freedom to the average energy. For an ideal gas, the state is governed by the ideal gas law PV = nRT, which connects microscopic motion to macroscopic observables.

Real gases depart from ideal behavior at high pressure or low temperature, where interparticle forces and finite particle sizes become important. Equations of state, such as the van der Waals equation, provide corrections. Gasteilchen thus underpin both fundamental theories of thermodynamics and practical calculations in chemistry and engineering.