Question

Solve the following from the introduction to the thermodynamics of materials (5.12 only part (b) and (c) sixth edition

5.12 Determine the values of AU', AH, AS', AA', and AG for the following pro- cesses (in (c), (d), and (e), show that an absolute value of the entropy is required): a. The four processes in Problem 4.1 b. The expansion of 1 mole of an ideal gas at the pressure P and the tempera- ture T into a vacuum to double its volume c. The adiabatic expansion of 1 mole of an ideal gas from P, T, to P, T, d. The expansion of 1 mole of an ideal gas at constant pressure from V, T, to V2, T2 e. The expansion of 1 mole of an ideal gas at constant volume from P, T, to P2, T2

Problem: 4.1 A rigid container is divided into two compartments of equal volume by a partition.
One compartment contains 1 mole of ideal gas A at 1 atm, and the other
contains 1 mole of ideal gas B at 1 atm. Calculate the increase in entropy which
occurs when the partition between the two compartments is removed. If the first
compartment had contained 2 moles of ideal gas A, what would have been the
increase in entropy when the partition was removed? Calculate the corresponding
increases in entropy in each of the preceding two situations if both compartments
had contained ideal gas A.

Answer 1

(ашми, nal pv state a state 1 Temperature - T Pressure op volume v All = oow :.su = CUOT = 0 . ..OT=0 Hence T₂ =T P, VI = P2V2 A5 = Eplm - Relom pa = -8.314 km (5.) - 5.7625/1 AH - MCPAT = 0 Af - AU - TAS 6(-8.3147.66(+) = -5.762x1 kJ 46 = SH - TAS =(-8.3147 In ( ) = -5.762x1 kJ

о) де" For adiabatic process from Piot, to P₂, Tz au = $*W EU = b = (P. V, - P2V 2) Y-1 All = mc ulT2-T,) as = mc, en T2 - MR in Pa AH = mcp (T2-T,) os = dQ = 0 imeplom Af = MC,(T2-T,) AG - MCP(1,-1,) As mix = - R & Gilingi - iti z its ..AS = - Rly knyA + Yalny) = -R(-0.693) = 5.7624 kJIK Of nA =2, yaz yo sitas AS = -R(ya enya + Yg en y B) E-R(-0.27031 – 0.3662) = 5.2919 kJ/K