Last modified: Mon 01/25/2016 09:48:49 am

Oklahoma State University

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Answer all of the questions below. If you do not know an answer enter CNA. However, it will help me the most if you answer each question with your best intuition/idea about what would be a reasonable answer.

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1. For each of the following reactions predict the sign of S.

a. CS2(l) + 3O2(g) ---> CO2(g) + 2SO2(g)

b. NH4NO2(s) --heat--> N2(g) + 2H2O(g)

c. KNO3(s) --H2O(l)--> K+(aq) + NO3-(aq)

2. Calculate rxn for the following reactions. (Here is a table that includes absolute entropies.) (Note: Use the mathematical relationship Also check Sample Problem 20.2 on page 823 in your textbook for a sample problem of this type. Watch out, elements have nonzero absolute entropy values. Be sure to check the table above.)

a) C2H5OH(l) + 3O2(g) ---> 2CO2(g) + 3H2O(l) J mol-1 K-1

b) H2(g) + F2(g) ----> 2HF(g) J mol-1 K-1

3. Is there anything about the questions that you feel you do not understand? List your concerns/questions.

4. If there is one question you would like to have answered in lecture, what would that question be?