Express z in terms of a and b ?
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Compressibility factor of gases is a thermodynamic property which is used to modify the ideal gas equation for real gases.
For Ideal gases,
PV = nRT
For real gases,
PV = ZnRT, (Z is the compressibility factor for the given gas)
The compressibility factor of a gas depends on the particular gas as well as temperature and pressure conditions.
Various equations of state can be used for calculation of compressibility factor of a gas as a function of temperature and pressure. Using different equations of state, various equations are derived for compressibility factor calculation. The constant parameters used in these equations are empirically determined for a gas.
Compressibility charts express compressibility factor values as a function of reduced temperature and reduced pressure.
Reduced temperature, Tr = T / Tc
Reduced pressure, Pr = P / Pc
where Tc and Pc are critical temperature and pressure values respectively.
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