Propane (1) and n-pentane (2) are binary vapor mixtures at a pressure and temperature of 1.0 bar and 100°C, respectively. Determine the fugacity coefficient as a function of composition. Sketch the calculated values for compositions of 1.0, 0.8, 0.6, 0.4, 0.2, and 0.0. Justify your answer. The virial coefficients for substances (1) and (2) are listed in Table 2.
B1 = 235
B2 = -684
B12 = -399
Table 2: Virial coefficients for substances (1) and (2).