gasvolumen

Gasvolumen is the volume that a given amount of gas occupies or would occupy under specified conditions. Because gases are highly compressible, their volume depends on pressure, temperature, and composition. For a fixed amount n of gas, the relation PV = nRT (the ideal gas law) describes how pressure P and temperature T determine the volume V. In general, the gas volume increases with temperature and decreases with pressure. The concept is central to chemistry, physics, and the energy industry, where gas quantities are often expressed at reference conditions known as standard conditions. Common units are cubic meters (m^3) and liters (L); for imperial units, cubic feet (ft^3). The molar volume of an ideal gas at standard temperature and pressure (STP) is about 22.414 L per mole; at room temperature (about 25°C) it is roughly 24.47 L per mole, assuming 1 atm. Real gases deviate from the ideal law, particularly at high pressures or low temperatures; the deviation is described by the compressibility factor Z, where PV = ZnRT.

In practice, gas volume is measured or reported with reference to standard conditions, and often corrected to those conditions using expansion factors. In the natural gas industry, billing uses standardized volumes adjusted to defined reference conditions. Gas volume measurement can be performed with volumetric meters, including positive-displacement and turbine meters, depending on gas properties. The concept also underpins safety calculations, ventilation design, and environmental monitoring.

See also: gas laws, molar volume, standard conditions, compressibility.