Gasdissolving

Gasdissolving is the process by which gas molecules disperse into and become solute within a liquid, reaching an equilibrium between the gas phase and the dissolved phase. The extent of dissolution depends on gas properties (solubility, molecular size), solvent properties (polarity, temperature), and conditions such as pressure and agitation. Henry's law governs dilute gas–liquid systems: the concentration of dissolved gas is proportional to its partial pressure in the gas phase, with a temperature-dependent constant. Kinetic factors include mass transfer across the gas–liquid interface, diffusion within the liquid, mixing, and surface area.

Temperature generally reduces gas solubility; increasing temperature drives dissolved gas back into the gas phase. Increasing pressure increases dissolution for most gases. Solubility varies widely: carbon dioxide dissolves readily in water under pressure, whereas noble gases are less soluble. Common coefficients used to describe solubility include Henry's law constant, the Bunsen solubility coefficient, and the Ostwald coefficient.

Exchange between phases also occurs as gases outgas when conditions change, such as depressurization or warming. In natural waters, equilibration with the atmosphere sets a baseline dissolved gas concentration, and biological or physical processes can consume or produce gases, altering local levels. Applications include carbonation of beverages, dissolved oxygen in aquatic systems, and industrial gas absorption or stripping. Measurement relies on gas partial pressures, concentration, and temperature data to estimate solubility via Henry’s law or empirical correlations. Limitations arise at high pressures or with non-ideal solutions, where deviations from Henry’s law occur and activity coefficients become important.