(a) The normal boiling point of carbon tetrachloride (CCl,) is 76.5°C. A student looks up the standard enthalpies of formation of CCI,(C) and of CCl,(g) in Appendix D. They are listed as -135.44 and -102.9 kJ mol!, respectively. By subtracting the first from the second, she computes AH° for the vaporization of CCl, to be 32.5 kJ mol-1. But Table 12.2 states that the AH,ap of CCl, is 30.0 kJ mol-!. Explain the discrepancy. (b) Calculate the molar entropy change of vaporization (AS,ap) of CCl, at 76.5°C.

(a) The normal boiling point of carbon tetrachloride (CCl,) is 76.5°C. A student looks up the standard enthalpies of formation of CCI,(C) and of CCl,(g) in Appendix D. They are listed as -135.44 and -102.9 kJ mol!, respectively. By subtracting the first from the second, she computes AH° for the vaporization of CCl, to be 32.5 kJ mol-1. But Table 12.2 states that the AH,ap of CCl, is 30.0 kJ mol-!. Explain the discrepancy. (b) Calculate the molar entropy change of vaporization (AS,ap) of CCl, at 76.5°C.

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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