CHELOGO

ChE421

Chemical Engineering Thermodynamics, Fall, 2008


 


I. COURSE OBJECTIVES

At the end of the semester, students are expected to


II. INSTRUCTOR AND MEETING TIMES

Instructor: Professor Wei-Yin Chen

Office: Room 140, Anderson Hall
Telephone: 915-5651
E-mail: cmchengs@olemiss.edu
Class: 4:15 pm - 5:45 pm, Tuesdays and Thursdays
Recitation Sessions: 1:30 p.m. - 2:30 p.m. Monday
Office Hour: 3:00 - 5:30 pm Wednesdays and Fridays, or by appointment
 

III. TEXTBOOKS:


IV. REFERENCES:


V. Exams/Tests/Homework:

There will be two hourly exams, and one final exam.  Homework will also be assigned every week, and the exam problems will be in similar nature of, but not be verbatim from, the homework assignments.
 

VI. Grading:

Homework 200 points
Hourly Exams 200 points
Final Examination 200 points
___________________________________________
Total 600 points

Total grade will be given according to a scale similar to the following:
600 < A < 480
479 < B < 420
419 < C < 360
359 < D < 300
299 < F
Depending on examination difficulty, this scale may be relaxed.

Because the level of difficulties of the materials, attendance is very important for the course.  In accordance with Departmental policy, students missing more than 9 class periods are subject to direct grade penalties. Penalties may be assessed without regard to the student's performance.

Students are expected to keep up with the material as it is presented and submit assignments on time; most students find this difficult without regular class attendance.  Successful learning involves the following important steps

    1. Attend all classes and listen carefully
    2. Do not fall sleep
    3. Do not hesitate to ask questions in or out of the classroom
    4. Do not play crosswords
    5. Practice, practice and practice
 
 

VII. TENTATIVE COURSE SCHEDULE
 
Number 

of Week

Week of  Topics Reading Assignments
1 August 24 Introduction & review of first law of thermodynamics Chapter 1 and 2
2 August 31
Volumetric properties of pure fluids Chapters 3
3 September 7
Volumetric properties of pure fluids Chapter 3
4 September 14
Heat effects  Chapter 4
5 September 21
Second law of thermodynamics, Exam I Chapter 5
6 September 28 Thermodynamic properties of fluids Chapter 6
7 October 5
Thermodynamic properties of fluids Chapter 6
8 October 12
VLE: introduction  Chapter 10
9 October 19 Solution thermodynamics: theory ( instructor in Taiwan) Chapter 11
10 October 26 Solution thermodynamics: theory;  Exam II Chapter 11
11 November 2
Solution thermodynamics: applications Chapter 12
12 November 9
Solution thermodynamics: applications Chapter 12
13 November 16 Solution thermodynamics: applications and Chemical-reaction equilibria
(AIChE annual meeting, instructor in Philadelphia)
Chapters 12 & 13
14 November 23
Fall Break :)
15 November 30
Chemical-reaction equilibria Chapter 13
16 December 7
Final Exam - 4:00 PM, Wednesday, December 10


 

VIII. MATHCAD PROGRAMS

Download MathCad programs: MCPH, ICPH, MCPS, ICPS, MDCPH, IDCPH, MDCPS, IDCPS, HRB, SRB, and PHIB: (v.2001i format)
http://home.olemiss.edu/~cmchengs/CHE421/programs.mcd
 
 

IX. HOMEWORK ASSIGNMENTS

Chapter 2: #1, #11, #27, #30, #33, and the problem below:
"A constant-volume bomb of capacity 0.028 m^3 contains an ideal gas at a pressure of 10 bar and a temperature of 311 K.  Connected to the bomb is a capillary tube through which the gas may slowly leak out into the atmosphere.  Surrounding the bomb and capillary is a water bath, which keeps the bomb and the its contains at 311 K.  Find the quantity of heat exchanged between the bath when gas no longer escapes from the bomb.  The gas has a constant Cp of 30 kJ / (kmol K)."
Ans:
    #1   a) 1.71 kJ,  b) 1.71 kJ,  c) 20.02 degC,  d) -1.71 kJ,  e) 0
    #11  0.929 hr
    #27  578.82  R
    #30  a) 11014 kJ,  b) -18.62 kJ
    #33  Ws=-172.99 Btu/lbm (Is the kinetic energy change negligible? yes!), or power=39.52 hp
    Extra problem:  Q = 25.2 kJ

Chapter 3: #5, #10, #21, #32, #44, #47, #54, Use Lee / Kesler as #32(f)
Ans:
    #5  W=18.302 atm ft^3
    #10  a) 2982 kJ,  b) 5105 kJ,  c) 7635 kJ,  d) 13200 kJ,  e) 1100 kJ
    #21  148.8 C
    #32  a) V = 1919 cm^3/mol, Z=0.929,
             b) V = 1924 cm^3/mol, Z=0.932,
             c) V = 1916.5 cm^3/mol,
             d) V = 1918 cm^3/mol, Z=0.928,
             e) V = 1900.6cm^3/mol, Z=0.92.
             f) V from Lee/Kesler = ?
    #44  m_liq = 127.6 kg, m_vap = 2.3 kg
    #47  Use one of the following methods:
             a)  trial-and-error with Lee/Kesler: 79.73 bar
             b)  R-K EOS:  85.29 bar
    #54  Use of the following methods
             a)  Figure 3.16: 0.629 gm/cm^3
             b)  Lee/Kesler: 0.638 gm/cm^3

Chapter 4: #2(a), #9(for n-pentane only), #21(b,c), #22(a), #26, #29, #31
Ans:
    #2(a)   1374.5 K
    #9 a) 358.6 J per gm, 5.05%,  b) 358.6, -0.4%
    #21 b) -905.468 kJ,  c) -71.660 kJ
    #22(a)  -109.795 kJ
    #26   -333.509 kJ
    #29  heat lost from the furnace = 70.612 kJ, heat transferred to the heat exchanger = 766.677 kJ
    #31  -115,653 J

Chapter 5: #7, #8, #21, #28(b); and #30
Ans:
    #7   max power = 5.336*10^6 kW,  Q = 8.538*10^6 kW
    #8   entropy change of water = 1.305 kJ/(kg K), entropy change of reservoir = -1.121 kJ/(kg K), total entropy change = 0.184 kJ/(kg K).
    #21 2.914 J / mol*K
    #28(b)   entropy change = 2657.5 J / K
    #30  total entropy change = 3.42 J/(mol K); it is positive, thus, the process is possible.

Chapter 6: #7, #17, #29, #49, #57, #58, #63, #64, #65, #81, #87(a)            Derive equations #24, #34 and #36 in the Chapter 6 of the notes.
Ans:
    #7     DS = -2.661 J / (kg K),  DH = 551.7 J / kg
    #17   a) entropy change = 100.34 J/(mol K),  b) 102.14 J/(mol K).
    #29   0.299 Btu/(lbm R)
    #49   a)  Gl = -89.94 Btu/lbm,  Gv = -89.91 Btu/lbm
             b)  DHlv/T = DSlv  =  1.055 Btu/(lbm R)
             c)  VR = -0.235 ft^3/lbm,  HR = -28.5 Btu/lbm,  SR = -0.0273 Btu/(lbm R)
             d) DSlv = 1.056 Btu/(lbm R)
                Generalized Charts: VR = -0.189 ft^3/lbm,  HR = -19.03 Btu/lbm,  SR = -0.0168 Btu/(lbm R)
    #57   T = 408.91 K,  DS = 24.699 J/(mol K)
    #58   DH = -801.9 J/mol, DS = -20.639 J/mol*K
    #63   T = 381.41 K, Ws = 5678 J/mol
    #64   Wmax = -1224.3 kJ/kg
    #65   Frac = 0.4058, DSsurr = 50.234 kW/K*s, DSsystem = -50.234 kW/K*s, DStotal = ?
    #81   Msteam = 3.933 lbm/s, DS = 2.064 BTU/R*s
    #87(a)   VR = -192 cm^3/mol,  HR = -1.429 kJ/mol,  SR = -0.002 kJ/(mol K)

Chapter 10: #2(a), #16, #26, #29
Ans:
#2 (a) Please see the graphical results at the end of this section.
#16  (a) 43.846 to 56.745 kPa,  (b) P = 51.892 kPa, molar fraction of vapor = 0.379  (c) no azeotrope, please explain.
#26  and #29  Similar to Examples 10.4 through 10.6 in the textbook.  Please use spreadsheet for your calculations.

Chapter 11: #1, #2, #17, #21, #23(a), #24(b), #25
Ans:
    #1   DS = 5.079 J / (mol K)
    #2   DS = 38.27 J / K
    #17   f = 217.14 bar,  G^E / RT = -0.323
    #21  f / f^sat = 1.079
    #23 (a)  f = 2.445 bar
    #24 (b)  See the graphical results at the end of this section.
    #25  (a)  f1 = 10.053 bar, f2 = 17.059 bar, phi1 = 0.957, phi2 = 0.875,
            (b)  f1 = 9.978 bar, f2 = 17.022 bar, phi1 = 0.95, phi2 = 0.873.

Chapter 12: #3, #13, #15, #18, Prove that the two forms of Margules equation can be transformed into each other, #26, #36, #37, #47, #50
    For #13 through #18, calculations should be conducted for the 1-propanol (1) / water (2) system
Ans:
  #3:  a) root-mean-square (RMS) error = 3.805kPa,  b) RMS = 3.137kPa,  c) RMS = 1.615kPa,
         d) RMS = 1.632kPa,  e) 1.629kPa,  f) 1.566kPa.  Please draw the fihures.
   #13  See the graphical results at the end of this section.
   #15  See the graphical results at the end of this section.
   #18  (a) T_bubble = 361.07 K, y1 = 0.419, y2 = 0.581
           (b) T_dew = 364.29 K, x1 = 0.048, x2 = 0.952
           (c) V = 0.805, x1 = 0.089, y1 = 0.351
           (d) T_azeotrope = 360.85 K, x1 = 0.4561
   #26  V1bar = 124.76 cm^3 / mol, V2bar = 93.36 cm^3 / bar
   #36  x_LiCl = 0.1012
   #37  It drops, approximately, from -67 to -79.5 kJ/mol when n increases from 10 to 1000.  Draw the figure.
   #47  205 F
   #50  By trial-and-error: m = 120 lb, (or 0.37 wt%), enthalpy of the mixture = -5.5 Btu /lb.

Chapter 13: #3, #4, #11, #16, and #32
Ans:
#3  See the results shown at the end of this section.#4  See the graphical results at the end of this section.
#11 yHCl = 0.3508,  yO2 = 0.0397,  yH2O = 0.3048,  yCl2 = 0.3048.
#16 (a) fractional conversion is 0.777,  (b) 646.8 K.
#32 (a) No, but why?   (b) No, but why?  (c) ratio = 4.1  (d) No, but why?
 

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