€ - gaadey) 01 Bueys ojy Hoday “snts Fuwivys ayy 10 dtjqnd o (e P Sur IR 1o npa @Ol 1w pasatosd 1y3usdos sugy 1sod 108 o (ueisuod 7y 10y 6ge, 15102 7 40) 6£0°01-) jowBypy g9z 10WS/f 6SL°€5€8 [OW/W [$0020°0 = [OW/E, WD 1400 = £0/¢ ) 10wBY/ Y 65.°¢ W+ Av=nv 801 -= "HV+'HV = HY ssoo0ud 304 ouw/f 68 10U/ 6L0°01- = HV 1241 Jo dey Yuq A woy 140t = /do anfea Suisn Ud) = (udl-"Hv="nv 10w 60,8801 -=.22°D[="HV [enwousjod do Suisp amssarg weisuo) :fj doig 0="2V 0="HV ammaduwia | umsuo) ¢ doig Latl ¥ T AEpouL 18 d ™ bbb = 1910601453 =NV S-= 0'8EEE-TIILT=HV BYNY0'1LST = BaN £0°D 081 ),0 BV T'19L2 = (PN £0°D 051 ) 1 BV 1°910€ = (RaIN § BYPE0'REEE = (BaN $°€ D 05k ) 1 " BdW §°€ pue 9 06 wouy abueyd ajess e sa06 Jepun weas (20'2) Y0S"TL = 99S0TAE 680L 000TT) = g HV WA JHw-f) =bos 9980 = 4o HV * BN €6'80L = H * 110002 HG W T9E°E = (FEO100°0 - TS9'1)eT = AV B/, 789'1 ~uonwodiony affuss &G aiqe pawatRns WOy 5,057 U TN 910 10 A 8£0100°0 $Z0100°0 | 6£0100°0 1101000 001 FE0100°0 €6 ST0100°0 L20100°0 08 89| <
g/kgmol ~ AH =-602.709 kl/kg ( 59 for Cp constant) AU =-464.098 ki/kg (421 for Cp constant) (2.08) Five grams of the specified pure solvent. For parts a-d neglect effect of pressure on H's. H =RHAY(T-298.15)+B"*(T°-298.15%)2+C*(T° - 208.1 where superscripts L denote liquid Cp parameters HY= [ CtaT + AH™ +[ crar R¥*(A(T-298.15)+ BT, 298.1 Since we only know AH'™ at boiling point, use ?)/2+CL¥(T,* - 298.1 and T is A(T- ToHB*(T- Ty )2+CH(T - Ty )3+ DX(T - Ty )4 superscri| 303.150r323.15K moles of benzene, n moles of ethanol, n (5 g/MW MW pis L denote liquid Cp parameters, where T, is the nors 5/78.15 = 6.4E-2 moles 5/46.07 = 0.1085 moles 57 30 or323.15K + AH™ + moles of water, n = (5 g)/ MW = 5/18.02 = 0.2775 moles 14,83 /g from all values read. To 3 & ac! 3 J/g 77 For part d). to change the reference state to 25C, subtract ll‘ at 30°C, H™- = (125.73- obtain enthalpy in J/mol, multiply by 18.02 g/mol. Example at : 104.83)*18.02 = 377 J/mol d water sant a tor water 2 roeve ehanol ethanol woler water i = T i 03,15 32315 30315 m; Sre0l 278601 A 31666 assee 8712 B s ATIEOT 47301 125E03 1IED: a 3.49E-04 3.49E-04 1.80E-07 -1.80E-07 5 9014 9014 3224 3224 8 2.14E-01 2.14E-01 1.92E-03 1.92E-03 :: -8.39E-05 -8.39E-05 1.06E-05 1.06E-05 o 1.37€-09 137E-09 -3.60E-09 -3.60E-09 ™ wies s Fafs 1S s6270 200202 37710 188789 37662 188327 655186 655186 568120 568129 38580 38580 40856 40656 040223 204480 237725 470181 4172963 4308706 43060.04 4463538 441610744 44806.0092 AH= 334842 329172 4116693 4018504 4358203 4274749 4378536 4zezate 1740056 1967047 2114616 2299454 2216857 2326163, 2226030 2334454 111364 125891 2294.36 249491 6151.78 6455.10 6179.73 547814 75% vaporized o)) 576267 2776840 14 E M RS TRR MY W% wwn sses s swsw = 584 534 942071 9217.34 94559 neglect the effect of pressure on e temperature, 1 bar = 750 mm Hg). Po not post this co Jelliott@uakron, ed, Vi e ateri B 0 Pyright protected materia] on public or file sharing sites. Report file sharit? W Chapter 2 uor lira@ egr.msu.edu mal boilir poir atin K, and T is nthalpies (however, note tha pressure does affect the satura!i
W‘j‘ I /V/ A ice... 0.6958m’/kg V' =0.5524mkg, W {2.11) One kg of steam in a piston/cylinder dev a) AU=Q-PAV, U'=2727. TkI/kg. U’ 67.5 ki/kg, V' -PAV 8)kJ/k; 50.2 kikg Q= (2567.5 2727.7)-502 = 210.4 Kk . ) b) need to find P where V' = 0.6958 at 150°C, between 0.2 and 0.3 MP: 0.281, at this pressure U ke, W=0AU=25722-2 a, interpolating, P* i jum is isotherm (2.12) In one stroke of a reciprocating compressor, helium is isothermally compressed ... Assume Ideal Gas 1 mol AU+ -+ dQ+dW, +dW,, where isothermal (4U = 0) = - 5704.8204 J/gmol 5704.8204 J/gmol 7 = 7 5704.8204 J/gmol Heat Removed = ~0 (2.13) Air at 30 C and 2 MPa enters a throttle with a velocity of 25m/s and exits at w 0.3MPa. The pipe diameter does not change. Compute T°, u°"", = Et E-balance AH'+ /g = 0, put enthalpy on a mass basis, Cp=T*RI(20.0288) = 1010 1 Cp(T™ - ") + (™ -0 10107 - 306182 + (' 1) M-balance V=ud, i : = _ R RIS (2.1 o pel 2] o). iz T 1819, = ) W =T1.819 (2) Solving (1) and (2) sim & 2) simultaneously with Exc, - temperature drop is abou |2 xeel, 7™ =29]1 K,y = T he temperatire rop g o2 C: T Problemn used very high veloe T b) s negligibl fo an gl . Y locities. Normally the Do 10t post this copyrig D B Jelliot
e— . {2.14) Argon at 400K and 50 bar is adiabatically... Cp=52R RICp=2/5 Ty = Ty(Py/P)" " = 400(1/50) 83.7K Wy = AH = Cp(T; - T)) = (5*8.314/2)(83.7-400) = -6574 kJ/mol _ (2.15) Steam at 500 bar and 500 C undergoes a throttling expansion ... < For Joule-Thomson expansion: ~ AH = Hf - Hj=0 Pj =500 bar = 50 MPa; Tj = 500°C; H' (50 MPa; 500°C) 6ki/kg (Steam Tables) H'=H'=2722.6 kl/kg, P'= | bar=0.1 MPa T' = (H"- 2675.8)/(2776.6 - 2675.8)(150-100) + 100 = 123.2°C For an ideal gas case: Enthalpy is a function of Temperature only H(T),Py)=H(T5,P2) becomes H(T()=H(T2) Which implies T;=T-=500 C Steam is very non-ideal under the given inlet conditions. (2.16) An adiabatic turbine operates... mAH = Wy = 750 kW = s (2865.9 - 3451.6) ki/kg., i = 1.28 ki (2.17) A steam turbine expands steam from 500 C, 3.5 MPa to 200°C and 0.3MPa. W=1750kW and Q = 100kW, what is mass flow? Ebal:0 = m" H" — ™ H™ +Q + W, W, =-750 kW 0 =-100kW = =0 H™at 200 °C, 0.3 MPa = 2865.6 ki/kg 3 H"at 500 °C, 3.5 MPa = 3451.6 ki/kg u -850 = = a [H™ —H") o (2.18) (a) P"" = 80bar steam is throttled to 1 bar and 400°C. Compute T". E (b) P = Thar (satLiq) is throttled to 1bar. Compute ¢°“. 2 o b a @) 0=H +O+W, ;e where 9=, =0 e S =g = :Illyih pressurc - H*(at 1 bar, 400 °C) = 3278.6 ki/kg 4 T"(at H" = H"and § MPa) = 452.1 °C valve b) _Du not post this copyright protected material on public or file sharing sites. Report file sharing to Jelliott@uakron.edu or lira@egr.msu.edu Chapter2 - 7 n— A
{2.14) Argon at 400K and 50 bar is adiabatically... R Cp RICp .4 p Ty = Ty(Po/Py)¥P = 400(1/50) = 83.7K Wa = AH = Cp(T: - T;) = (5*8.314/2)(83.7-400) = -6574 kJ mol (2.15) Steam at 500 bar and 500 C undergoes a throttling expansion ... For Joule-Thomson expansion: AH = Hf - Hi =0 Pj =500 bar = 50 MPa; Tj = 500°C; H' (50 MPa; 500°C) =2722.6 ki/kg (Steam Tables) H=H .6 kI/kg, P= 1 bar = 0.1 MPa T' = (H' 2675.8)/(2776.6 - 2675.8)(150-100) + 100 = 123.2°C thalpy is a function of Temperature only. becomes H(T;)=H(T:) Which implies T=T,= 500 C. For an ideal H(T,.P)=H( Steam is very non-ideal under the given inlet conditions. (2.16) An adiabatic turbine operates... mAH=Ws = 750 kW = /i (2865.9 - 3451.6) ki/kg, i = 1.28 kg/sec (2.17) A steam turbine expands steam from 500 C, 3.5 MPa to 200°C and 0.3MPa. W=750kW and @ = 100kW, what is mass flow? Ebal:0= " H" — ™ H"™ + 0 + W. - 750 kW - 100 kW H*"at 200 °C, 0.3 MPa = 2865.6 kl/kg > H"at500°C, 3.5 MPa = 3451.6 ki/kg u -850 ) s —————=1.45 kg/sec 3 =7 - (2.18) (a) P = 80bar steam is throttled to 1 bar and 400°C. Compute T". (b) P" = Tbar (satLiq) is throttled to 1bar. Compute ™. a) 0=H"-H"+0+W. . whee Q=W =0 £ e~ Highpressre H"(at 1 bar, 400 °C) = 3278.6 ki/kg - T"(at H" = H*"and 8 MPa)=452.1 °C b) Do ot post this copyright protected material on public or file sharing sites. Report file sharing to jelliott@uakron.edu or lira@egr.msu.edu Chapter2 -7
i i and two (2.19) An overall balance “around part of a plant involves three inlets | outlets which only contains water Balance dn a10.15 MPa, g = 0.9) H,= 461.1 +(0.9%2229.5) = 2467.6 ki/kg .8 MPa) #,=2768.3 klkg 3072.1 ki’kg 943.1) - 30(2467.6) —120 =163015 KJ/min =2716.9 kW s SoL {2.20) Steam at 550 kPa and 200C....a) En, A H®=H™ p s interpolating between 0.5 and 0.6 MPa e H® = 0.5(2855.8 + 2850.6) v Froin: At p 853 at 0.2 MPa t P T revert interpolation formula at 0.2 MPa ! 2769.1 + x(2870.7-2769.1), x = 0.83, T= 150+ 0.83(50)=191°C A e = b) Energ U +0.83(2654.6 1) =2641 kl/kg Ul U™=0.5(2642.9 + 2638.9) = 2641 ki’kg V0. 1mp AU =0 even though AT = -9°C. —— DG ot po jellion@u, . . “nort file Domot post this copyright protected material on public or file sharing sites. Report 00 Jelliott@uakron.edu or lira@ egr.msu.edu
It leaks to 1bar. S37) A 0.1 m® cylinder is initially at 10 bar and 300K. : =4.01 mols @2 0 300K, n, = PY/RT = 0. 1MPa(0.1E6cm’)/8.314/300 Ty(P/PY P =300(1/10) = 1554K 7,) = (7*8.314/2)(155 4-300) = 4208 kJ. mol 2.22) As part of a supercritical extraction of coal ... ba U-n H (™ — m™); w'=0=m"™ = ol=m", U=H",PF 20 MPa, s 20MPa, 400°C, H” = 2816.9 kJ/mol s s between 450 and 500°C. Interpolating, 6.9 - 2807.2)/(2945.3 - 2807.2) * 50 = 453 y interpolation, m = ¥/ = 1/0.01286 his V2 Hdn™ - H™dn™; ndU = (H"-H)(dn/dt)dt, G G (), dt ) [2.24) An adiabatic tank of negligible heat capacity ... pen Unsteady System: AUm = HAm+ 0+ =t he = . 0 m' H" = U/ =H" Table. H"(1 MPa, 200°CY =1 MPa and U=2828.3 kI/k LIc 684m’ / kg kikg 73 kg balance: A(Um)=HAm +Q+W - U'm'= H5(m' - m') VA0.1MP=.150°C) = 1.9367 m'/kg and U' 0t post this copyright protected material on public or file sha e: i uskron.edu or lira@egr.msu.edu 4 SRR fi('?hiha""wg “:) apter 2 -
rt a) me as pal ‘. which in principle canlt:»cqfiifi_‘: ;.l e )’ and V', Howcwr._n s quickey H")(U-H )r‘i mula for U an ngv‘i"c function, v ‘J( U on for ing as an obj cvare e i l’t‘:‘l o “gglr:er. the temperature ca g " Using G al Seek or S 0 g Goal ). Using Note: w, If w, enging, intg v, dellioe 544