ABSTRACT
The methods to calculate fugacities described in Chapter 13 assumed the availability of equations of state valid from zero pressure to the pressure of the system at the temperature and composition of the system. While for systems in the gas phase this is a reasonable assumption, for condensed mixtures, this is not always the case. The volumetric behavior of an aqueous solution of sugar, for example, is not easily described from the ideal gas to the liquid phase using a single equation of state. However, the fact that we do not have an analytical expression to handle the algebra does not mean that the thermodynamic relations between the thermodynamic properties are not valid. Although in this chapter we develop relations of general use, we concentrate mostly on cases when the pure compounds forming a mixture exist as liquids at the temperature T and pressure P of the system. Hence, using Equation 13.9, https://www.w3.org/1998/Math/MathML"> ln ϕ i ( T , P , x ) ϕ i 0 ( T , P ) = 1 R T ∫ 0 P [ v ¯ i − v i 0 ] d P https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9781315399065/5df30985-80c1-4e11-9533-10c20ed2604c/content/equ13_09a.tif" xmlns:xlink="https://www.w3.org/1999/xlink"/>
