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ECHE 311/SPRING 2015 Problem Set # 9 Similar Problems will be given in Exam 2 1. The following is set of activity-coefficient data for the binary liquid system as determined by VLE. x1 1 0.0523 0.1299 0.2233 0.2764 0.3482 0.4187 0.5001 1.202 1.307 1.295 1.228 1.234 1.180 1.129 2 x1 1.002 1.004 1.006 1.024 1.022 1.049 1.092 0.5637 0.6469 0.7832 0.8576 0.9388 0.9813 1 2 1.120 1.076 1.032 1.016 1.001 1.003 1.102 1.170 1.298 1.393 1.600 1.404 Inspection of these experimental values suggest that they are noisy, but the question is whether they are consistent, and therefore possibly on average correct. (a) Find experimental values for values of G E / RT and plot them along with the experimental ln 1 and ln 2 on a single graph. E (b) Develop a valid correlation for the composition dependence of G / RT and show lines on the graph of part (a) that represent this correlation for all thee of the quantities plotted there. (c) Apply the consistency test described bellow and in Example (11/Fifth Edition SVNA) to these data and draw a conclusion with respect to this test. 2. The total enthalpy of a binary liquid system of species 1 and 2 at fixed T and P is given by: See Example 11.4 in your textbook (page 389) H=400x1+600x2+x1x2 (40x1+20x2) a) Apply Eq (11.7 in your textbook) to Equation A in the Example to verify Eqs (B) nad (C). Find expression for the molar enthalpies of species 1 and 2. b) Show that Eqs (B) and (C) combine in accord with Eq. (11.11) to regenerate Eq. A. c) Show that these expressions satisfy the Gibs/Duhem equation. d) Plot values of H, H 1(x1) and H 2(x2) calculated by equations (A), (B), (C) vs. x1 . 3. Solve Problems 11.19; 11.23 from your textbook