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|07.06 Solving The Cubic EOS for Z||Click here.||68||5||
5. Peng Robinson Using Solver for PVT and Vapor Pressure - Excel (4:42) (msu.edu)
Describes use of the Goal Seek and Solver tools for Peng-Robinson PVT properties and vapor pressure.
1. Which of the following represents the vapor pressure for argon at 100K?
|13.01 - Local Composition Theory||Click here.||68||10||
Local Composition Concepts (6:51) (msu.edu)
The local composition models of chapter 13 share common features covered in this screencasts. An understanding of these principles will make all the algebra in the models less daunting.
1. In the picture of molecules given in the presentation on slide 2, what is the numerical value of the local composition x11?
|13.02 - Wilson's Equation||Click here.||66.6667||6||
Wilson's model concepts (2:44) (msu.edu)
The background on the assumptions and development of Wilson's activity coefficient model.
1. What value is assumed by Wilson's model for the coordination number (z)?
|11.02 - Calculations with Activity Coefficients||Click here.||65||4||
This example shows how to incorporate activity calculations into Excel for solutions that follow the Margules 1-parameter (M1) model.(9min, uakron.edu)
You should be able to adapt this procedure along with the procedure for the multicomponent ideal solutions to create a multicomponent M1 model. If you are having trouble, the video for the multicomponent SSCED model illustrates a very similar procedure. You can check your answers by putting in the same component twice. For example, instead of an equimolar binary mixture, input a quaternary mixture with 0.25 moles of methanol, 0.25 methanol (ie. type it as if it was another component), 0.25 of benzene and 0.25 of benzene. If you don't get the same results as for the binary equimolar system, check your calculations.Note: This is a companion file in a series. You may wish to choose your own order for viewing them. For example, you should implement the first three videos before implementing this one. Also, you might like to see how to quickly visualize the Txy analog of the Pxy phase diagram. If you see a phase diagram like the ones in section 11.8, you might want to learn about LLE phase diagrams. The links on the software tutorial present a summary of the techniques to be implemented throughout Unit3 in a quick access format that is more compact than what is presented elsewhere. Some students may find it helpful to refer to this compact list when they find themselves "not being able to find the forest because of all the trees."
Comprehension Questions: Assume the SCVP model (Eq. 2.47).
|04.02 The Microscopic View of Entropy||Click here.||65||4||
Principles of Probability I, General Concepts, Correlated and Conditional Events. (msu.edu, 17min) (Flash)
|04.02 The Microscopic View of Entropy||Click here.||65||4||
Principles of Probability II, Counting Events, Permutations and Combinations. This part discusses the binomial and multinomial coefficients for putting particles in boxes. The binomial and multinomial coefficient are used in section 4.2 to quantify configurational entropy. (msu.edu, 16min) (Flash) You might like to check out the sample calculations below before attempting the comprehension questions.
|05.5 Liquefaction||Click here.||60||2||
Joule-Thomson Expansion (LearnChemE.com, 7min) describes the Joule-Thomson coefficient - (dT/dP)H. For non-ideal fluids (including liquids), the temperature usually drops as the pressure drops. From a molecular perspective, it requires energy to rip molecules apart when they are in their attractive wells, and this energy must be taken from the thermal energy of the molecules themselves if the system is adiabatic. This video refers to the PREOS.xls spreadsheet to be used more in Unit II, but you can get the idea of how the Joule-Thomson expansion provides a basis for any liquefaction of any chemical, including the liquefaction that occurs in refrigeration and the one that occurs in a process designed to simply recover liquid product (e.g. liquefied natural gas (LNG), aka. methane).
1. Referring to the table for R134a in Appendix E-12, compute the fraction liquid at 252K after throttling from a saturated liquid at 300K.
2. Referring to the table for R134a in Appendix E-12, compute the fraction liquid at 252K after expanding a saturated liquid at 300K through a reversible turbine.
|08.08 - Reference States||Click here.||60||2||
Thermodynamic pathways of EOS's for arbitrary reference states (uakron.edu, 20min) The development of a thermodynamic pathway from an arbitrary reference state to a given state condition is independent of the thermodynamic model. It depends only on (1a) identifying the condition of the reference state (e.g. ideal gas, real vapor, or liquid) (1b) transforming from the reference state to the ideal gas, if necessary (2) transforming from the ideal gas at the condition of the reference state to the ideal gas at the given state condition (3a) identifying the condition at the given state (3b) transforming from the ideal gas at the given state to the real fluid at the given state. The methodology is illustrated for two thermodynamic models: the Psat/Hvap model of Figure 2.6c,Eqs 2.45,47 vs. the PR EOS. The screencast is a bit long, but it covers 16 sample calculations (8 for H and 8 for S) and comparisons between PREOS vs Psat/Hvap. You might like to refer back to Sections 2.10 and 3.6 to review the Psat/Hvap model and the elemental reference state. Push pause before each sample calculation and check whether you can predict the next answer.
1. Compute "H" by hand for propane at 80C and 3 MPa relative to a reference at 230K and 1bar, assuming Cpig/R = 8.85 and the PR EOS. You may use PREOS.xlsx to compute H-Hig, but you must show your hand calculations for each step (1a-3b). Compare your answer to the result tabulated in PREOS.xlsx.
|10.03 - Binary VLE using Raoult's Law||Click here.||60||2||
Raoult's Law (5:39) (msu.edu)
|09.10 - Saturation Conditions from an Equation of State||Click here.||60||2||
Solving for the saturation pressure using PREOS.xls simply involves setting the temperature and guessing pressure until the fugacities in vapor and liquid are equal. (5min, learncheme.com) It is not shown, but it would also be easy to set the pressure and guess temperature until the fugacities were equal in order to solve for saturation temperature. One added suggestion would be to type in the shortcut vapor pressure (SCVP) equation to give an initial estimate of the pressure. Rearranging the SCVP can also give an initial guess for Tsat when given P. This presentation illustrates a sample calculation for toluene to explore when the vapor is the stable, when the liquid is the stable phase, and when the phases are roughly in equilibrium.
1. Estimate the vapor pressure (MPa) of n-pentane at 450K according to the PREOS. Compare your result to the value from Eq. 2.47 (SCVP) and to the Antoine equation using the coefficients given in Appendix E. What do you think explains the observations that you make?