# PS7 - 1 = 0.1, using: (a) The one-parameter Margules...

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ChBE 3110, Fall Semester, 2009 Chemical Engineering Thermodynamics II Problem Set Seven 1. Two similar liquids form a miscible solution for which the G E may be well represented by a one-term Margules equation, G E = Ax 1 x 2 , where A is a constant. Data (300ºK): A = 1000 cal/gmole; P 1 s = 800 torr; P 2 s = 500 torr (a) Find the limiting activity coefficients, γ 1 and γ 2 . (b) Use a spreadsheet to plot γ 1 and γ 2 vs x 1 . (c) Use a spreadsheet to plot P 1 , P 2 and P Total vs x 1 (d) Does an azeotrope exist at 300ºK. (e) What are the pressure and composition of this azeotrope? 2. The compositions of coexisting phases of ethanol(1) + propanol(2) at 55 o C are x 1 =0.7186, and y 1 =0.7431 at P =307.81 mmHg, as reported by Kretschmer and Wiebe, J. Amer. Chem. Soc. , 71, 1793(1949). Estimate the bubble pressure at 55 o C and x
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Unformatted text preview: 1 = 0.1, using: (a) The one-parameter Margules equation (b) The two-parameter Margules equation (c) The van Laar equation 3. Using the van Laar model and the following data estimate the total pressure and composition of the vapor in equilibrium with a 20 mol% ethanol(1) solution in water(2) at 78.15 o C. Data at 78.15 o C: 1 2 1 2 1.006 bar 0.439 bar 1.6931; 1.9523 sat sat p p γ ∞ ∞ = = = = 4. A single P-x 1-y 1 data point is available for a binary system at 25 o C. Estimate from the data: (a) The total pressure and vapor-phase composition at 25 o C for an equimolar liquid mixture. (b) Whether azeotropy is likely at 25 o C. Data at 25ºC: P 1 sat = 183.4 kPa; P 2 sat = 96.7 kPa For x 1 = 0.253, y 1 = 0.456, and P total = 139.1 kPa...
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## This note was uploaded on 10/18/2009 for the course CHBE 3110 taught by Professor Staff during the Spring '08 term at Georgia Institute of Technology.

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