3. (20 points) In section 16.2.7, Dandekar describes drawbacks of the ideal mixture principle, and states that K values cannot be estimated by using the ideal mixture principle for temperatures above the critical temperature of the most volatile component of the mixture. However, this statement is not entirely correct a. (10 points) Please disprove the above statement of Dandekar by using Equation 16.25 for plotting the bubble and dew points for the mixture used in Figure 16.2 (Page 446) from 100F to 250F. That is, please make a PT diagram that shows Po and Pd points based on Equation 16.25 for the temperature range. b. (10 points) Part a serves as a disproof because Equation 16.25 is indeed based on the ideal mixture principle (i.e., Raoult's law). Explain how this is the case. Question References Equation 16.25: In 1968, Wilson proposed a simplified thermodynamic expression for estimating the equilibrium ratio values, having the following functional form: P. K= - [3740+ a)( - ) cap (16.25) where K is the equilibrium ratio of component i Po is the critical pressure of component i P is the system pressure 0; is the acentric factor of component i To is the critical temperature of component i Tis the system temperature In Equation 16.25, pressures and temperatures in any absolute units can be used. And Figure 16.2: 700 600- 500 A from Equation 16.19 Pa from Equation 16.23 Phase envelope from EOS Critical point Te isotherm of propane 400- Pressure, psia 300 200- 100 100 0+ 0 50 150 200 250 300 Temperature, "F FIGURE 16.2 Comparison of bubble- and dew-point pressures calculated by the ideal mixture principle and an EOS model for ternary mixture of 60 mol-% propane, 30 mol-% n-butane, and 10 mol-% -pentane