Chemical Engineering Thermodynamics

Transcription

1 Engi-3434 Chemical Engineering Thermodynamics Dr. Charles Chemical Engineering, Lakehead Universiy Chemical Engineering Thermodynamics Insrucor: Dr. Charles Xu, P.Eng. Associae Professor Deparmen of Chemical Engineering Office: CB 1043 Phone: cxu@lakeheadu.ca Office Hours: Wednesday, -4 PM Lecures: Monday & Wednesday 10:00 AM 11:30 AM AT-005 Tuorials: Friday :30 PM 4:00PM, saring from he nd week of he lecure SN-011 Course Websie: hp://flash.lakeheadu.ca/~cxu/engi3434.hm 1 Required Texbook Inroducion o Chemical Engineering Thermodynamics Sevenh Ediion Smih Van Ness Abbo

2 Topics o be Discussed Inroducion and Fundamenals of Thermodynamics (Chaper 1) The Firs Law of Thermodynamics for Close and Open Sysems (Chaper ) Equaion of Sae (Chaper 3) Hea Effecs (Chaper 4) The Second Law of Thermodynamics (Chaper 5) Thermodynamic Properies of (Pure) Fluid (Chaper 6) Vapour-Liquid Equilibrium (Chaper 10) Theory of Soluion Thermodynamics (Chaper 11) Chemical Reacion Equilibrium (Chaper 13) 3 Grading In-class Quizzes 10% Assignmens 0%* Miderm Examinaion 30% Final Examinaion 60% * Soluions will be posed on he course websie. 4

3 Abou he Course Noes All course noes (EXCEPT for soluions o some example problems) will be available on he course websie: Course Websie: hp://flash.lakeheadu.ca/~cxu/engi3434.hm Please download, prin ou and sudy he course noes before he lecure ime and complee he noes if needed during he lecure ime. 5 Course Policy Saemen Quizzes: Quizzes will be given in class a randomly imes hroughou he course o reinforce lecure and assignmens conceps. The average of he quizzes couns 10% of he overall grade. No make-up quizzes will be given expec ha a valid wrien excuse (e.g., a docor s noe, ec.) will be submied and approved by he insrucor. Assignmens: Abou 4 ~ 5 assignmens will be given during he course. The soluions will be posed on he course websie. Thus he assignmens will no be marked.. 6

4 Why o Sudy Thermodynamics? A Chemical Engineer imaged by he Insrucor Chemical Process and Plan Design Mah Mass & Hea Transfers Chemisry Fluid Dynamics Process Conrol Economics, Ehics.. Compuer Thermodynamics Reacion Kineics, Reacion eng. & reacor design The Scope of Thermodynamics Hea and work required for physical and chemical processes Measuremen, esimaion, and correlaion of hermodynamic properies Transfer of chemical species beween phases Equilibrium condiions for chemical reacions Thermodynamics does NOT discuss he raes of chemical or physical processes! 8

5 Some Basic Relaions in Thermodynamics Firs law: ΔE Q + W + E( flow) + E( gen) Second law: ΔS Phase equilibrium relaions: Q + S( flow) + S( gen) T f$ f$ f$ α β π i i i Chemical reacion equilibrium: RT ln K ΔG o K fˆ f i 0 i ν i 9 1. Dimensions & Unis Dimension SI Uni English Uni Reference for SI Uni Time second, s The duraion of 9,19,631,770 cycles of radiaion associaed wih radioacive decay of he Cesium aom Disance meer, m foo, f (1 f m) (1 m f) Mass kilogram, kg pound mass, lb m (1 lb m kg) (1 kg.046 lb m) Temperaure Kelvin, K Amoun of subsance gram mole, g mole Rankine, R T(R) 1.8 T (K) pound mole, lb mol (1 lb mol g mol) Disance ha ligh ravels in a vacuum during 1/99,79,458 of a second Mass of a plainum/iridium alloy cylinder kep in he Inernaional Bureau of Weighs and Measures a Sevres, France 1/76.16 of he hermodynamic emperaure of he riple poin of waer (i.e. he sae of waer in which liquid, solid and vapor coexis a equilibrium) Amoun of subsance ha conains as many elemenary eniies as here are aoms in 0.01 kg of carbon-1 ( , which is Avogadro's number) 10

6 Dimensions & Unis (Con d) Measures of Amoun and Size Three basic measures Mass, m (kg) Number of moles, n (mol) Toal volume, V (m 3 ) Four derivaives Specific volume, V V (m 3 /kg) m Molar volume, V (m V 3 /mol) n Specific densiy, m 1 ρ (kg/m 3 ) V V Molar densiy, n 1 ρ (mol/m 3 ) V V 1

7 Newon s nd Law (SI unis): 1.4 Force F ma Where: F is force (Newon, N kg ms - ), defined as ha force which acceleraes 1 kg mass 1.0 ms - m is mass (kg) a is acceleraion (ms - ), 1 ms (f)(s) -. The acceleraion of graviy a g 9.81 ms - Newon s nd Law (English unis): F 1 g ma c Where: F is pound force (lb f ). 1 lb f represens he force ha acceleraes 1 lb m mass a a (f)(s) - m is mass (lb m ) a is acceleraion (fs - ) g c (lbm)(f)(lbf) -1 (s) - 1 lb f N Can you prove i? 13 Temperaure Scales 1.5 Temperaure The Celsius scale: 0 C and 100 C correspond o he ice poin (freezing poin) and he seam poin (boiling poin) of pure waer a sandard amospheric pressure. The Fahrenhei scale: ( F ) 1.8 ( C ) + 3 or ( C ) [ ( F ) 3] 5/9 The Kelvin scale (absolue emperaure): T (K) ( C ) The Rankine scale: T (R) 1.8 T (K) T (R) ( F ) Anders Celsius ( ) Daniel Gabriel Fahrenhei ( ) William Thomson ( ) The Kelvin scale William John Macquorn Rankine 14 ( )

8 Example 1.1 An asronau weighs 730 N in Houson, Texas, where he local acceleraion of graviy is g 9.79 ms -. Wha are he asronau s mass and weigh on he moon where g 1.67ms -. (a) Solve he problem in SI unis. (b) Wha are acceleraion of graviies in English unis in Houson and on he moon? (c) Solve he problem in English unis. Soluions (a) Soluion in SI unis Newon s nd Law (SI unis): F ma When a g, he force from he Newon s law is he force of graviy or weigh, i.e., F mg - F 730 N 730 kgms m 74.55kg g 9.79 ms 9.79 ms Mass is independen of locaion, bu he weigh depends on he locaion (wih differen local acceleraions of graviy)! Thus The mass on he moon is he same as in Houson, i.e., m (moon) kg The weigh on he moon is - F (Moon) mg (moon) 74.55kg 1.67 ms 14.5 kgms N 1 m (f) Example 1.1 (Con d) (b) g in English unis Conversion facors of SI unis o English unis m f g in Houson is g f / s s 1m g on he Moon is m f g f / s s 1m (c) Soluion in English unis 1lbf N 1 N 0.5 (lbf ) 0.5 lb Weigh of asronau in Houson is f F 730 N 164.1lbf 1 N 1 Newon s nd Law (English unis): F ma g -1 F g c 164.1(lbf ) (lbm )(f)(lbf ) (s) m (Moon) m (Houson) g(houson) 3.13 (f)(s) m(moon) g(moon) (lbm ) 5.48 (f)(s) F (Moon) -1 g (lb )(f)(lb ) (s) c c m f (lb ) f (lb m ) 16