Chem. 444, Fall 2006 Name: ____________________________ Instructor: Nancy Makri SECOND HOUR EXAM November 3, 2006 1. State whether the temperature T of the system, the entropy sys S of the system and the entropy tot S of the universe (i.e., that of the system and its surroundings) increase, decrease or remain constant during each of the processes described below. In each case justify your answer in a single sentence. (a) Reversible isothermal expansion of an ideal gas. (b) Free expansion of an ideal gas. (c) Reversible adiabatic compression of an ideal gas. (20 points) 2. A fluid (not necessarily an ideal gas) is expanded and heated, such that its temperature is changed from 1 T to 2 T and its volume is changed from 1 V to 2 V . Express an infinitesimal change of the entropy in terms of infinitesimal changes in the temperature and volume. You can evaluate the change in entropy by integrating this differential form. However, derivatives of the entropy are not measurable directly. Therefore, you should first transform this relation to bring it in a form that
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