Not at Steady State! Yes! Only if reactions occur! Yes! Ideal Gas, change in temperature or pressure. Yes! Class 15. Is the following possible?

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Miles Bryan
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1 Chapter 5-6 (where we are gong) Ideal gae and lqud (today) Dente Partal preure Non-deal gae (next tme) Eqn. of tate Reduced preure and temperature Compreblty chart (z) Vapor-lqud ytem (Ch. 6) Vapor preure Humdty Raoult law Bubble and dew pont Sold-old & lqud-lqud ytem Cla 15 Properte of Sngle Phae Materal Connecton to Materal Balance Ideal Aumpton Lqud- denty of mxture Ideal Gae Standard condton I the followng poble? I the followng poble? 30 kg 20 kg 30 mole 20 mole Not at Steady State! Ye! Only f reacton occur! I the followng poble? I the followng poble? 20 cm 3 pure lqud A 30 cm 3 / 20 cm 3 / No Chemcal Reacton 40 cm 3 pure lqud B Mxer (no reacton) 55 cm 3 mxture Ye! Ideal Ga, change n temperature or preure Ye! Even for lqud ytem! 1

2 Need Relatonhp Between Varable Not eay to meaure molar flow rate What can we ealy meaure? Ma flow rate Volumetrc flow rate Compoton Preure Temperature Relate meaured varable to dered quantte Lqud Mxture In general, lqud volume not conerved V = V 1 + V 2 + V E Contracton or expanon occur becaue of the dfference n nteracton between lke and unlke molecule V E typcally mall. Aume V E = 0 for th coure. Th mple that lqud volume are addtve n 1 x 1 x = ma fracton of pece x Ma and Mole Fracton Have Unt! Look at unt of denty equaton 1 / 1 n x (ame wth mole) Example What the denty of a mxture contanng 20 wt% A ( A = 1 g/cm 3 ) and the balance B ( B = 2 g/cm 3 )? A B 1 Therefore, = 1.67 g/cm If you ued = x, you would have calculated = 0.2* *2 = 1.8 g/cm 3. Oop! Gae Ideal Ga Equaton of State (EOS) relate amount (mole) to V, T, P Many dfferent equaton of tate repreent behavor of real ytem Ideal Ga Law Smplet equaton of tate Mot wdely ued Equaton of State: PV = nrt Alo P Vˆ = RT (.e., Vˆ = V/n) Aumpton No nteracton between molecule Molecule have zero volume Vald at low concentraton (n/v) Bet at hgh or low preure? Bet at hgh or low temperature? V = pecfc volume 2

3 Ideal v. Real Gae Ideal Ga Contant P In Chemtry and Chemcal Engneerng, R unveral (ndependent of pece) Nce table n the back cover of the book for dfferent unt In Mechancal Engneerng, the MW of the pece ncluded, o there a dfferent value of R for each pece From p. 221, deal when: Vˆ deal 5L / mol ( datomc gae) Vˆ 20L / mol ( other gae) deal Doe th make ene? Ideal Ga Contant from CRC Handbook }For deal ga eqn } For Energy or or Ga Concentraton & Denty Concentraton = mole/volume = n/v C n V P RT or y P Denty = ma/volume = nmw/v = CMW n MW P MW V RT C RT or yp MW RT Applcaton Example Suppoe the tre on your car are nflated to 32 pg at 25 o C (77 o F). What the tre preure at -10 o C (14 o F)? Aume that you are at ea level. Would th make a dfference n your anwer? Concept: # mole do not change! PV PV Tme Saver! 1 2 n P 2 /T 2 = P 1 /T 1 RT1 RT2 Mut ue abolute P and T P 1 = 32 pg pa =46.7 pa P 2 = P 1 (T 2 /T 1 ) = 46.7 pa * (263 K/298 K) = 41.2 pa = 26.5 pg If P atm = 12.5, P 2 = 39.3 pa = 26.8 pg 3

Tom Brady & Deflate-Gate T = 72F ndoor (532R) T = 10F Outdoor (470R) V = contant Regulaton: 12.5 to 13.5 pg contant P P 12.5 pg 27.2 pa 470 R 532 R 24.0 pa 9.3 pg 11.9 pg f tartng preure wa 13.

4 Tom Brady & Deflate-Gate T = 72F ndoor (532R) T = 10F Outdoor (470R) V = contant Regulaton: 12.5 to 13.5 pg contant P P 12.5 pg 27.2 pa 470 R 532 R 24.0 pa 9.3 pg 11.9 pg f tartng preure wa 13.5 pg Concept: # mole do not change! V contant Cauton Only take rato of value n abolute unt NEVER take rato of: Temperature n C or F (ntead ue K or R) Gauge preure (ntead ue abolute preure) Ued frequently by author Standard Condton Provde a reference pont for reportng ga flow Convenent for ue n calculaton wth deal ga law Unt generally reported by flow meter SI T = 0 o C = 273K P = 1 atm V = m 3 ( L/mol) n = 1 gmol Amercan Engneerng T = 492 o R (.e., 32F) P = 1 atm V = 359 ft 3 /lb-mol n = 1 lb-mol Socety of Petroleum Engneer (common ndutral tandard) T = 60 o F P = 14.7 pa Ga Flow under Standard Condton SCM: tandard cubc meter (m 3 STP) SCF: tandard cubc feet (ft 3 STP) SCFM: tandard cubc feet per mnute (ft 3 /mn STP) SCMH: tandard cubc meter per hour (m 3 /hr STP) SCFH: tandard cubc feet per hour (ft 3 /hr STP) SCCM: tandard cubc centmeter per mnute (cm 3 /mn STP) SLPM: tandard lter per mnute (lt/mn STP) Ga Flow under Standard Condton SCM: tandard cubc meter (m 3 STP) SCF: tandard cubc feet (ft 3 STP) SCFM: tandard cubc feet per mnute (ft 3 /mn STP) SCMH: tandard cubc meter per hour (m 3 /hr STP) SCFH: tandard cubc feet per hour (ft 3 /hr STP) SCCM: tandard cubc centmeter per mnute (cm 3 /mn STP) SLPM: tandard lter per mnute (lt/mn STP) Frequently ued n Dr. Fletcher experence Standard Condton and Ideal Ga Calculaton PV nrt RT RT RT Concept: n doe not change! n doe not change! ( = tandard tate) o T T Gven tandard volume or volumetrc flow rate, ue rato to convert to actual volume or volumetrc flow rate PV PV T T 4

Flow Meter Often Report Standard Condton Example from my lab Example The flow rate of a tream at 285 o F and 1.3 atm meaured wth an orfce meter.

n PV RT P V RT o Abolute T Ma flow controller (lpm) Rotameter (lpm or ccm) P T 5 1atm 745 R 5 3 V V 3.95 10 SCFM 4.60 10 ft / mn P T 1.

p O2 = y O2 P tot = 0.21*1.0 atm = 0.21 atm Good for both deal and non-deal gae! Ga Mxture (cont.

$25)(20 atm) = 5 atm Ideal Ga Mxture Amagat Law partal volume add up to total volume v A + v B + = V tot Volume fracton = mole fracton percent by volume = mole percent v$

5 Flow Meter Often Report Standard Condton Example from my lab Example The flow rate of a tream at 285 o F and 1.3 atm meaured wth an orfce meter. The calbraton chart for the meter ndcate that the flow 3.95 x 10 5 SCFM. Calculate the molar flow rate and the true volumetrc flow rate of the tream. n PV RT P V RT o Abolute T Ma flow controller (lpm) Rotameter (lpm or ccm) P T 5 1atm 745 R 5 3 V V SCFM ft / mn P T 1.3atm 492R Ga Mxture Partal preure of component A p A = y A P tot Dalton Law total P = um of partal preure Example: At ea level, what the partal preure of O 2? p O2 = y O2 P tot = 0.21*1.0 atm = 0.21 atm Good for both deal and non-deal gae! Ga Mxture (cont.) In LaBarge, Wyomng, there a natural ga well for ExxonMobl Ga compoton comng from the well : y CO2 = 0.70 y CH4 = 0.25 y H2S = 0.05 If the total preure n the well 20 atm, what the partal preure of CH 4? P CH4 = y CH4 P tot = (0.25)(20 atm) = 5 atm Ideal Ga Mxture Amagat Law partal volume add up to total volume v A + v B + = V tot Volume fracton = mole fracton percent by volume = mole percent v A = y A V tot Good only for deal gae! Problem 5.13 (purgng a box) N 2 V = 2 m 3 N 2 P = 10 cm H 2 O gauge T = 25C Replace volume every 5 mnute Fnd m (a) Calculate m ung the deal ga equaton (eay) (b) Calculate m ung 22.4 L/mol at tandard condton (th way confung) 5

6 HW Hnt 5.15 (5.11) ga cylnder Total ma = m tank + m ga m ga = n ga MW ga Wth contant volume at STP, n = contant 5.25 (5.19 workbook) 5.34 (5.25) Avg MW, ma fracton 5.36 (5.27) breathng Fnd V n, convert to m n N 2 balance, fnd m out and V out Body 6

No! Yes! Only if reactions occur! Yes! Ideal Gas, change in temperature or pressure. Survey Results. Class 15. Is the following possible?

No! Yes! Only if reactions occur! Yes! Ideal Gas, change in temperature or pressure. Survey Results. Class 15. Is the following possible? Survey Reult Chapter 5-6 (where we are gong) % of Student 45% 40% 35% 30% 25% 20% 15% 10% 5% 0% Hour Spent on ChE 273 1-2 3-4 5-6 7-8 9-10 11+ Hour/Week 2008 2009 2010 2011 2012 2013 2014 2015 2017 F17