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59-240 Physical Chemistry - Question Set #12 - Lecture 12 - v. 2.0 - updated Oct. 25, 2018Assigned questions for Lecture 12 are listed below. The questions occur in the followingeditions of “Physical Chemistry” by P.W. Atkins:11th edition10th edition9th edition8th editionNote: The letter “P” in front of a number indicates that the question is in the “Problem” categoryas opposed to the “Exercise” category in Atkins’ books. Updates are highlighted in yellow.There are a fair number of differences and missing questions, and unfortunately, a lot of goodproblems were removed years ago from earlier editions.Question 12.01*n/an/a3.63.6Missing from 10th and 11th Eds. (not sure why).3.6(a) Consider a system consisting of 2.0 mol CO2(g), initially at 25 C and 10 atm and confinedto a cylinder of cross-section 10.0 cm2. It is allowed to expand adiabatically against an externalpressure of 1.0 atm until the piston has moved outwards through 20 cm. Assume that carbondioxide may be considered a perfect gas with CV,m 28.8 J K-1 mol-1 and calculate (a) q, (b) w, (c)ΔU, (d) ΔT, (e) ΔS.3.6(b) Consider a system consisting of 1.5 mol CO2(g), initially at 15 C and 9.0 atm andconfined to a cylinder of cross-section 100.0 cm2. The sample is allowed to expand adiabaticallyagainst an external pressure of 1.5 atm until the piston has moved outwards through 15 cm.Assume that carbon dioxide may be considered a perfect gas with CV,m 28.8 J K-1 mol-1, andcalculate (a) q, (b) w, (c) ΔU, (d) ΔT, (e) ΔS.Question 12.023B.23A.113.73.73B.2(a) The enthalpy of vaporization of chloroform (CHCl3) is 29.4 kJ mol 1 at its normalboiling point of 334.88 K. Calculate (i) the entropy of vaporization of chloroform at thistemperature and (ii) the entropy change of the surroundings.3B.2(b) The enthalpy of vaporization of methanol is 35.27 kJ mol 1 at its normal boiling point of64.1 C. Calculate (i) the entropy of vaporization of methanol at this temperature and (ii) theentropy change of the surroundings.Question 12.033C.23.113.11Same question format, different compounds in the 10th and 11th Eds. vs. earlier editions.3.11(a) Calculate the standard Gibbs energy of the reaction 4 HCl(g) O2(g) 2 Cl2(g) 2 H2O(l) at 298 K, from the standard entropies and enthalpies of formation given in the Data section3.11(b) Calculate the standard Gibbs energy of the reaction CO(g) CH3 OH(l) CH3University of Windsor - Department of Chemistry and Biochemistry - R.W. Schurko1

59-240 Physical Chemistry - Question Set #12 - Lecture 12 - v. 2.0 - updated Oct. 25, 2018COOH(l) at 298 K, from the standard entropies and enthalpies of formation given in the Datasection.3C.2(a) Calculate the standard Gibbs energy of the reaction 4 HI(g) O2(g) 2 I2(s) 2 H2O(l)at 298 K, from the standard entropies and enthalpies of formation given in the Resource section3C.2(b) Calculate the standard Gibbs energy of the reaction CO(g) CH3CH2OH(l) CH3CH2COOH(l) at 298 K, from the standard entropies and enthalpies of formation given in theResource section. The data for CH3CH2COOH(l) are ΔfH -510 kJ mol-1, Sm 191 J K-1 mol-1at 298K.Question 12.043D.53C.53.123.12Same question format, different compounds in the 10th and 11th Eds. vs. earlier editions.9th Ed. and earlier:3.12(a) The standard enthalpy of combustion of solid phenol (C6H5OH) is -3054 kJ mol-1 at 298K and its standard molar entropy is 144.0 J K-1 mol-1. Calculate the standard Gibbs energy offormation of phenol at 298 K.3.12(b) The standard enthalpy of combustion of solid urea (CO(NH2)2) is –632 kJ mol-1 at 298 Kand its standard molar entropy is 104.60 J K-1 mol-1. Calculate the standard Gibbs energy offormation of urea at 298 K.10th and 11th Eds.:3D.5(a) The standard enthalpy of combustion of ethyl acetate (CH3COOC2H5) is 2231 kJ mol-1at 298 K and its standard molar entropy is 259.4 J K-1 mol-1. Calculate the standard Gibbs energyof formation of the compound at 298 K.3D.5(b) The standard enthalpy of combustion of the amino acid glycine (NH2CH2COOH) is 969 kJ mol-1 at 298 K and its standard molar entropy is 103.5 J K-1 mol-1. Calculate thestandard Gibbs energy of formation of glycine at 298 K.Question 12.053A.43A.103.133.13In the 11th Ed., the solutions manual omits the text in grey - I have am not sure why this is thecase, except that you do not really need the values of p to do these problems.3A.4(a) Calculate the change in the entropies of the system and the surroundings, and the totalchange in entropy, when a sample of nitrogen gas of mass 14 g at 298 K and 1.00 bar doubles itsvolume in (i) an isothermal reversible expansion, (ii) an isothermal irreversible expansion againstpex 0, and (iii) an adiabatic reversible expansion.3A.4(b) Calculate the change in the entropies of the system and the surroundings, and the totalchange in entropy, when the volume of a sample of argon gas of mass 21 g at 298 K and 1.50 barincreases from 1.20 dm3 to 4.60 dm3 in (i) an isothermal reversible expansion, (ii) an isothermalirreversible expansion against pex 0, and (iii) an adiabatic reversible expansion.University of Windsor - Department of Chemistry and Biochemistry - R.W. Schurko2

59-240 Physical Chemistry - Question Set #12 - Lecture 12 - v. 2.0 - updated Oct. 25, 2018Question 12.06*n/an/aP3.5P3.5Missing from the 10th and 11th eds. Not sure why.3.5 A Carnot cycle uses 1.00 mol of a monatomic perfect gas as the working substance from aninitial state of 10.0 atm and 600 K. It expands isothermally to a pressure of 1.00 atm (Step 1),and then adiabatically to a temperature of 300 K (Step 2). This expansion is followed by anisothermal compression (Step 3), and then an adiabatic compression (Step 4) back to the initialstate. Determine the values of q, w, ΔU, ΔH, ΔS, ΔStot, and ΔG for each stage of the cycle andfor the cycle as a whole. Express your answer as a table of values.Answer 12.01n/an/a3.63.6Missing from 10th and 11th Eds. (not sure why).University of Windsor - Department of Chemistry and Biochemistry - R.W. Schurko3

59-240 Physical Chemistry - Question Set #12 - Lecture 12 - v. 2.0 - updated Oct. 25, 2018University of Windsor - Department of Chemistry and Biochemistry - R.W. Schurko4

59-240 Physical Chemistry - Question Set #12 - Lecture 12 - v. 2.0 - updated Oct. 25, 2018Answer 12.06n/aP3.5P3.5Missing from the 10th and 11th eds. Not sure why.(continued next page)University of Windsor - Department of Chemistry and Biochemistry - R.W. Schurko5

59-240 Physical Chemistry - Question Set #12 - Lecture 12 - v. 2.0 - updated Oct. 25, 2018University of Windsor - Department of Chemistry and Biochemistry - R.W. Schurko6

3) is 29.4 kJ mol 1 at its normal boiling point of 334.88 K. Calculate (i) the entropy of vaporization of chloroform at this temperature and (ii) the entropy change of the surroundings. 3B.2(b) The enthalpy of vaporization of methanol is 35.27 kJ mol 1 at its normal boiling point of 64.1 C.