Question

study o OT-O expanded isothermally at 25°C from 24 2 dm3 to 48 4 dm according to the three processes described below For (b) A sample consisting of 1 00 mol of the molecules in air is 2each of the three processes calculate w q. AU, and AH Reversibly, () (5) (n) Against a constant external pressure (irreversibly) equal to the final pressure of the gas, and (m) Freely (against zero external pressure) (6) (1)

Answer 1

smce the atimal emogy of a AU 0 Fa all caseA onlytmperature PEofect gak depemel H= U t PV Dehinition of emdhalpy ACPV) AH AU + A CNRT) AH = poesses n peafect gas f8 all AH 0 at constamt temperalure (a AU -nRT In 48.4 dm -re)x(8 X 24.2dm3 .314 |- I.72 KJ 0-(-. 72Kg) AU-w +1.7 2KT (b) AU = AH = O (48.4-24.2)0 PeAV 24.2dm3 Can be omputid om th petct qs aw Pen nRT nRT Pex

( mol) x (o.08 206 dm3 atm k mol X298 K 48.4 dm2 O. 505 adm .013 x 10 pa x a4. 2 dm X 505 lo dm3 latm - . 24 X -1.24XL T - t.24KJ 1.24KJ 0t1.24 kJ AU U AU is expansion aainst no Faae expamsion amd AU - w = 0-0- peafect gas An fsdthurmalfae expansion cf a adiabatic also