2. Consider the following reaction: 4 HCN(/) + 5 O2(g) → 2 H₂O(g) + 4 CO₂(g) + 2 N2(g) (a) Using the following data, calculate AG," for this reaction at 25 °C. Compound AG (kJ/mol) AH (kJ/mol) Sm (J/mol-K) HCN(/) +124.7 +108.87 112.84 O2(g) 205.138 N2(g) 191.61 H₂O(/) -237.13 -285.83 69.91 H2O(g) -228.57 -241.82 188.83 CO2(g) -394.39 -393.51 213.74 (b) At this temperature, in which direction is this reaction spontaneous? How do you know? (c) At what temperature, in °C, does this reaction become spontaneous in the opposite direction? (d) If the standard chemical potential at SATP of H2O(g) is -16.5 kJ mol¹, what is the chemical potential of H2O(g) at 75. kPa, in kJ/mol? What does this tell you about the potential of H2O to participate in chemical activity as the pressure is changing?

2. Consider the following reaction: 4 HCN(/) + 5 O2(g) → 2 H₂O(g) + 4 CO₂(g) + 2 N2(g) (a) Using the following data, calculate AG," for this reaction at 25 °C. Compound AG (kJ/mol) AH (kJ/mol) Sm (J/mol-K) HCN(/) +124.7 +108.87 112.84 O2(g) 205.138 N2(g) 191.61 H₂O(/) -237.13 -285.83 69.91 H2O(g) -228.57 -241.82 188.83 CO2(g) -394.39 -393.51 213.74 (b) At this temperature, in which direction is this reaction spontaneous? How do you know? (c) At what temperature, in °C, does this reaction become spontaneous in the opposite direction? (d) If the standard chemical potential at SATP of H2O(g) is -16.5 kJ mol¹, what is the chemical potential of H2O(g) at 75. kPa, in kJ/mol? What does this tell you about the potential of H2O to participate in chemical activity as the pressure is changing?

Chemistry: Principles and Practice

3rd Edition

ISBN:9780534420123

Author:Daniel L. Reger, Scott R. Goode, David W. Ball, Edward Mercer

Publisher:Daniel L. Reger, Scott R. Goode, David W. Ball, Edward Mercer

Chapter17: Chemcial Thermodynamics

Section: Chapter Questions

Problem 17.109QE: Chemists and engineers who design nuclear power plants have to worry about high-temperature...

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For the reaction BaCO3(s) BaO(s) + CO2(g), rG = +219.7 kJ/mol-rxn. Using this value and other data available in Appendix L, calculate the value of fG for BaCO3(s).
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