TUIUWING substances using AG C, IUI eacH Of the = AHp - T ASº a) C2H4 (g) b) C2H5OH (1) 4. For the reaction: C2H2 (g) + 2 H2 (g) → C2H6 (g) , calculate AHº, AGº, ASº and Keg at 25°C. Also, calculate Keg for this same reaction at 75°C. 5. A mixture consisting of 100 moles of hydrogen gas and 2500 moles of air (80.0 mol % nitrogen gas and 20.0 mol % oxygen gas), initially at 25ºC, reacts to produce water vapor (and no nitrogen oxides). The pressure is constant atl atm, and the system is adiabatic (no heat exchange between the system and surroundings). The molar heat capacities are: 5.9 cal/mol•C for water vapor; 6.9 cal/moloC for N2 and 02. Calculate the maximum temperature achieved by this system. Answers: 1. a) -136.98 kJ/mol C2H4; b) -58.02 kJ/mol N2O4; c) -1299.53 kJ/mol C2H2 2. AH = -121.99 kJ 3. a) 69.46 kJ/mol; b) -166.3 kJ/mol 4. At 25ºC, AHº = -311.38 kJ; ASº = -232.46 J; AGº = -242.09 kJ; %3D %3D %3D %3D

TUIUWING substances using AG C, IUI eacH Of the = AHp - T ASº a) C2H4 (g) b) C2H5OH (1) 4. For the reaction: C2H2 (g) + 2 H2 (g) → C2H6 (g) , calculate AHº, AGº, ASº and Keg at 25°C. Also, calculate Keg for this same reaction at 75°C. 5. A mixture consisting of 100 moles of hydrogen gas and 2500 moles of air (80.0 mol % nitrogen gas and 20.0 mol % oxygen gas), initially at 25ºC, reacts to produce water vapor (and no nitrogen oxides). The pressure is constant atl atm, and the system is adiabatic (no heat exchange between the system and surroundings). The molar heat capacities are: 5.9 cal/mol•C for water vapor; 6.9 cal/moloC for N2 and 02. Calculate the maximum temperature achieved by this system. Answers: 1. a) -136.98 kJ/mol C2H4; b) -58.02 kJ/mol N2O4; c) -1299.53 kJ/mol C2H2 2. AH = -121.99 kJ 3. a) 69.46 kJ/mol; b) -166.3 kJ/mol 4. At 25ºC, AHº = -311.38 kJ; ASº = -232.46 J; AGº = -242.09 kJ; %3D %3D %3D %3D

Chemistry

9th Edition

ISBN:9781133611097

Author:Steven S. Zumdahl

Publisher:Steven S. Zumdahl

Chapter13: Chemical Equilibrium

Section: Chapter Questions

Problem 10RQ: The only stress (change) that also changes the value of K is a change in temperature. For an...

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