Consider the reaction CS2 (g) + 4H2 (g) = CH4 (9) + 2H,S(g) a. Calculate AH°,AS°, and AG° at 25°C for this reaction. AH; (kJ/mol) S° (J/mol·K) CS2 (g) 116.9 237.9 130.6 H2 (9) CH4 (9) -74.87 186.1 H,S(g) -20.50 205.6 ΔΗ. kJ AS° = J/K AG° kJ b. Assume AH° and ASº are constant with respect to a change of temperature. Now calculate AG° at 250°C. AG kJ %3D c. Compare the two values of AG°. What can you say about the spontaneity of the reaction at 25°C and at 250°C? The reaction will be spontaneous at 25°C, and it will be nonspontaneous at 250°C. The reaction will be nonspontaneous at 25°C, and it will be spontaneous at 250°C. The reaction will be spontaneous at both 25°C and 250°C. The reaction will be nonspontaneous at both 25°C and 250°C.

Consider the reaction CS2 (g) + 4H2 (g) = CH4 (9) + 2H,S(g) a. Calculate AH°,AS°, and AG° at 25°C for this reaction. AH; (kJ/mol) S° (J/mol·K) CS2 (g) 116.9 237.9 130.6 H2 (9) CH4 (9) -74.87 186.1 H,S(g) -20.50 205.6 ΔΗ. kJ AS° = J/K AG° kJ b. Assume AH° and ASº are constant with respect to a change of temperature. Now calculate AG° at 250°C. AG kJ %3D c. Compare the two values of AG°. What can you say about the spontaneity of the reaction at 25°C and at 250°C? The reaction will be spontaneous at 25°C, and it will be nonspontaneous at 250°C. The reaction will be nonspontaneous at 25°C, and it will be spontaneous at 250°C. The reaction will be spontaneous at both 25°C and 250°C. The reaction will be nonspontaneous at both 25°C and 250°C.

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 10.14PAE: Enthalpy changes often help predict whether or not a process will be spontaneous. What type of...

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