molar volume
molar volume :
A unit used by chemists and physicists to measure the volumes of gases. The behavior of gases under ordinary conditions (not at very high pressures or very low temperatures) is governed by the Ideal Gas Law. This law says that the volume V of a gas is related to its temperature T and pressure P by the formula PV = nRT, where n is the number of moles of gas present and the gas constant R equals 8.314 joules per mole per kelvin. The molar volume is the volume one mole of gas occupies at standard temperature (273.16 kelvins, or 0 °C) and standard pressure (1 atmosphere, or 101.325 kilopascals). The molar volume is equal to 22.414 liters or 0.7915 cubic foot. (Occasionally the term "molar volume" is used for the volume occupied by a mole of a substance which is not a gas; in such cases the molar volume will be different for each substance.)
