Define the term entropy, and give an example of a sample of matter that has zero entropy. What are the units of entropy? How do they differ from the units of enthalpy?

What is entropy? Why is entropy important?

Explain why the statement No process is 100 efficient is not the best statement of the second law of thermodynamics.

Explain why absolute entropies can be measured.

What are the two ways that a final chemical state of a system can be more probable than its initial state?

For each process, tell whether the entropy change of the system is positive or negative. (a) A glassblower heats glass (the system) to its softening temperature. (b) A teaspoon of sugar dissolves in a cup of coffee. (The system consists of both sugar and coffee.) (c) Calcium carbonate precipitates out of water in a cave to form stalactites and stalagmites. (Consider only the calcium carbonate to be the system.)

The standard molar entropy of methanol vapor, CH3OH(g), is 239.8 J K1 mol-1. (a) Calculate the entropy change for the vaporization of 1 mol methanol (use data from Table 16.1 or Appendix J). (b) Calculate the enthalpy of vaporization of methanol, assuming that rS doesnt depend on temperature and taking the boiling point of methanol to be 64.6C.

For one day, keep a log of all the activities you undertake that consume Gibbs free energy. Distinguish betweenGibbs free energy provided by nutrient metabolism andthat provided by other energy resources.

Determine the entropy change for the combustion of gaseous propane, C3H8, under the standard conditions to give gaseous carbon dioxide and water.