18. The standard enthalpy of formation (AHO) of benzoic acid (C6H5COOH) at 25°C is -385.1 kJ mol-¹. Using Kirchoff's Law, find AH°f of benzoic acid at 100 °C given the following heat capacities (Cp,m): C6H5COOH(s) = 146.8 J K-¹ mol-¹ C(graphite) = 8.527 J K-¹ mol-¹ H₂(g) = 28.83 J K-¹ mol-¹ O2(g) = 29.36 J K-¹ mol-¹ Assume these heat capacities are independent of temperature.

18. The standard enthalpy of formation (AHO) of benzoic acid (C6H5COOH) at 25°C is -385.1 kJ mol-¹. Using Kirchoff's Law, find AH°f of benzoic acid at 100 °C given the following heat capacities (Cp,m): C6H5COOH(s) = 146.8 J K-¹ mol-¹ C(graphite) = 8.527 J K-¹ mol-¹ H₂(g) = 28.83 J K-¹ mol-¹ O2(g) = 29.36 J K-¹ mol-¹ Assume these heat capacities are independent of temperature.

Chemistry: The Molecular Science

5th Edition

ISBN:9781285199047

Author:John W. Moore, Conrad L. Stanitski

Publisher:John W. Moore, Conrad L. Stanitski

Chapter4: Energy And Chemical Reactions

Section: Chapter Questions

Problem 65QRT

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