It is also known as the compression factor, is the ratio of the molar volume of a gas to the molar volume of an ideal gas at the same temperature and pressure The compressibility factor (Z), also known as the compression factor, is the ratio of the molar volume of a gas to the molar volume of an ideal gas at the same temperature and pressure.
For the topological property, see Incompressible surface. In thermodynamics and fluid mechanics, compressibility is a measure of the relative volume change of a fluid or solid as a response to a pressure (or mean stress) change. where V is volume and p is pressure. The term compressibility is also used in thermodynamics to describe the deviance in the thermodynamic properties of a real gas from those expected from an ideal gas. The compressibility factor is defined as. where p is the pressure of the gas, T is its temperature, and is its molar volume. In the case of an ideal gas, the compressibility factor Z is equal to unity, and the familiar ideal gas law is recovered: Z can, in general, be either greater or less than unity for a real gas The compressibility factor (Z), also known as the compression factor, is the ratio of the molar volume of a gas to the molar volume of an ideal gas at the same temperature and pressure. It is a useful thermodynamic property for modifying the ideal gas law to account for the real gas behavior. Figure 2 is an example of a generalized compressibility factor graph derived from hundreds of experimental PVT data points of 10 pure gases, namely methane, ethane, ethylene, propane, n-butane, i-pentane, n-hexane, nitrogen, carbon dioxide and steam. Figure 1: Example graphs of gas compressibility factors. The compressibility factor (Z) is a useful thermodynamic property for modifying the ideal gas law to account for behavior of real gases. It is a measure of how much the thermodynamic properties of a real gas deviate from those expected of an ideal gas. There are more detailed generalized compressibility factor graphs based on as many as 25 or more different pure gases, such as the Nelson-Obert graphs. Such graphs are said to have an accuracy within 1-2 percent for Z values greater than 0.6 and within 4-6 percent for Z values of 0.3-0.6. Process Associates Gas Compressibility Factor. The familiar and most commonly known gas law is. PVm = RT. And the non ideal corrected is. PVm = ZRT. In the above P = Pressure, Vm is volume (molar volume of gas) Z = the compressibility factor, R = the universal constand and T is for temperature. The compressibility factor is defined in statistical mechanics as. where p is the pressure, n is the number density, is the temperature in energy units (i.e. joules, by multiplication for the Boltzmann constant), and is the gas constant. Figure 2 is an example of a generalized compressibility factor graph derived from hundreds of experimental PVT data points of 10 pure gases, namely methane, ethane, ethylene, propane, n-butane, i-pentane, n-hexane, nitrogen, carbon dioxide and steam. There are more detailed generalized compressibility factor graphs based on as many as 25 or more different pure gases, such as the Nelson-Obert graphs. Such graphs are said to have an accuracy within 1-2 percent for values greater than 0.6 and within 4-6 percent for values of 0.3-0.6. Figure 2 is an example of a generalized compressibility factor graph derived from hundreds of experimental PVT data points of 10 pure gases, namely methane, ethane, ethylene, propane, n-butane, i-pentane, n-hexane, nitrogen, carbon dioxide and steam. The upper graph in Figure 1 illustrates how the compressibility factor varies for different gases at the same temperature and pressure. The lower graph illustrates how the compressibility factor of a gas (for example, methane) at a given pressure varies with temperature. There are more detailed generalized compressibility factor graphs based on as many as 25 or more different pure gases, such as the Nelson-Obert graphs. Such graphs are said to have an accuracy within 1-2 percent for Z values greater than 0.6 and within 4-6 percent for Z values of 0.3-0.6.
https://en.wikipedia.org/wiki/Compressibility https://en.wikipedia.org/wiki/Compressibility_factor http://www.tau.ac.il/~tsirel/dump/Static/knowino.org/wiki/Compressibility_factor_(gases).html http://www.processassociates.com/process/property/z_factor.htm https://en.wikipedia.org/wiki/Compressibility_factor https://en.wikipedia.org/wiki/Compressibility_factor http://en.citizendium.org/wiki/Compressibility_factor_%28gases%29
what is the compressibility factor