Gaschemie

Gaschemie, or gas chemistry, is the branch of chemistry that studies the properties, behavior, and reactions of gases, whether as pure substances or as components of mixtures. It covers thermodynamics, kinetics, and transport phenomena in gaseous systems, as well as gas-phase reactions important in industry, energy, and the environment.

Fundamental concepts include the behavior of gases described by the ideal gas law PV = nRT, the kinetic theory of gases, and the concept of partial pressures (Dalton’s law). Gas mixing, diffusion, and effusion are governed by molecular speeds and collisions. Real gases deviate from ideal behavior at high pressures or low temperatures; these deviations are described by more advanced equations of state, such as the van der Waals equation, and by the compressibility factor Z.

Gas-phase reactions and kinetics form a core area, including unimolecular and bimolecular reactions, reaction mechanisms, and catalytic processes. Collisional theory and transition-state concepts help explain rate laws. Techniques such as spectroscopy, gas chromatography, and mass spectrometry are used to analyze gaseous species and reaction mixtures. Industrially important gas-phase processes include ammonia synthesis (Haber process), methanol production, and oxidation and hydrocarbon conversion reactions.

Applications extend to environmental science, such as atmospheric chemistry and the study of greenhouse gases and ozone depletion, as well as safety and standards for handling compressed gases. Gaschemie thus intersects physical chemistry, chemical engineering, and environmental science.