Gibbs Free Energy Third Law of Thermodynamics Directions: Answer the following items 1. Calculate the standard free-energy changes for the following reactions at 25°C. a. CH49) + 202 - CO2@ + 2H2O b. 2MgOu) → 2Mg) + Ozg) 2. The molar heats of fusion and vaporization of benzene are 10.9 kJ/mol and 31.0 kJ/mol, respectively. Calculate the entropy changes for the solid → liquid and liquid vapor transitions for benzene. At 1 atm pressure, benzene melts at 5.5°C and boils at 80.1°C. 3. Using data listed in Table I below, calculate the equilibrium constant (K) for the following reaction at 25°C: 2H2Oa) → 2H2g) = Ozg) %3D Inorganic Substances AH°; (kJ/mol) AG°r (kJ/mol) -137.3 S° (J/K'mol) Substance CO CO22) H22) H2Ou Ozg) -110.5 197.9 -393.5 -394.4 213.6 131.0 -285.8 -237.2 69.9 205.0 Organic Substances CH4g) Mg) MgOs) Table 1. Table 1. Selected Thermodynamic Data at 1 atm and 25°C* -74.85 -50.8 186.2 32.5 -601.8 569.6 26.78 *The AH°s, AG; and S° values for ions are based on the reference states AH (H.) = 0, AGr (H.)3D0, and S (H.)%3D0.

Gibbs Free Energy Third Law of Thermodynamics Directions: Answer the following items 1. Calculate the standard free-energy changes for the following reactions at 25°C. a. CH49) + 202 - CO2@ + 2H2O b. 2MgOu) → 2Mg) + Ozg) 2. The molar heats of fusion and vaporization of benzene are 10.9 kJ/mol and 31.0 kJ/mol, respectively. Calculate the entropy changes for the solid → liquid and liquid vapor transitions for benzene. At 1 atm pressure, benzene melts at 5.5°C and boils at 80.1°C. 3. Using data listed in Table I below, calculate the equilibrium constant (K) for the following reaction at 25°C: 2H2Oa) → 2H2g) = Ozg) %3D Inorganic Substances AH°; (kJ/mol) AG°r (kJ/mol) -137.3 S° (J/K'mol) Substance CO CO22) H22) H2Ou Ozg) -110.5 197.9 -393.5 -394.4 213.6 131.0 -285.8 -237.2 69.9 205.0 Organic Substances CH4g) Mg) MgOs) Table 1. Table 1. Selected Thermodynamic Data at 1 atm and 25°C* -74.85 -50.8 186.2 32.5 -601.8 569.6 26.78 *The AH°s, AG; and S° values for ions are based on the reference states AH (H.) = 0, AGr (H.)3D0, and S (H.)%3D0.

Chemistry for Engineering Students

4th Edition

ISBN:9781337398909

Author:Lawrence S. Brown, Tom Holme

Publisher:Lawrence S. Brown, Tom Holme

Chapter10: Entropy And The Second Law Of Thermodynamics

Section: Chapter Questions

Problem 10.50PAE: For the reaction NO(g)+NO2(g)N2O3(g) , use tabulated thermodynamic data to calculate H and S. Then...

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