Calculate the difference in molar entropy (a) between liquid water and ice at -5 °C, (b) between liquid water and its vapour at 95 °C and 1.00 atm. The differences in heat capacities on melting and on vaporization are 37.3 JK-¹mol-¹ and -41.9 JK-¹mol-¹, respectively. Distinguish between the entropy changes of the sample, the surroundings, and the total system, and discuss the spontaneity of the transitions at the two temperatures.

Calculate the difference in molar entropy (a) between liquid water and ice at -5 °C, (b) between liquid water and its vapour at 95 °C and 1.00 atm. The differences in heat capacities on melting and on vaporization are 37.3 JK-¹mol-¹ and -41.9 JK-¹mol-¹, respectively. Distinguish between the entropy changes of the sample, the surroundings, and the total system, and discuss the spontaneity of the transitions at the two temperatures.

Principles of Modern Chemistry

8th Edition

ISBN:9781305079113

Author:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Publisher:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Chapter13: Spontaneous Processes And Thermodynamic Equilibrium

Section: Chapter Questions

Problem 46AP

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