As mentioned before, density is defined as the ratio of mass per unit volume of a material. Using a real gas law yields the following equation for gas density at a prevailing pressure and temperature. Here, MW is molecular weight, R is the universal gas constant, and Z is the gas compressibility factor.
In contrast with the liquid phase, the cubic EOSs give reliable gas densities. Therefore EOSs can be used as a suitable method for the determination of gas density.
220.127.116.11. Theoretical Determination of Gas Density
For the determination of gas density at a specified temperature and pressure, the ...