Last modified: Wed 12/31/1969 06:00:00 pm

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.

First Name:

Last Name:

Laboratory Section:

1a. Look at the table of vapor pressures at different temperatures and enter the eqilibrium vapor pressure for water at 80 °C and at 90 °C.

mmHg (80 °C)

mmHg (90 °C)

b) A sample of water in a container at 90 °C exerts a pressure of 500 mmHg. Explain why we can assume that the sample is only vapor/gas under these conditions of temperature and pressure.

c) If the container is cooled to 80 °C calculate the pressure exerted by the sample assuming the sample remains in the gas phase (use the ideal gas law P1/T1 = P2/T2). Also assume the volume is held constant and no water is lost. Be sure the temperature is in Kelvin not Celsius.


d) Based on you answer in Q1c and the equilibrium vapor pressure at 80 °C, indicate the phase(s) present in the container at 80 °C.

2. Solve each of the following; (NOTE: If you use scientific notation, enter 4.99 x 10-4 as 4.99e-4)

a) 1/298 K - 1/350 K = K-1

b) (-24000 J mol-1/8.314 J mol-1 K-1) * (1/298 K- 1/350 K) =

3. Isopropyl alcohol has an equilibrium vapor pressure of 91 mmHg at 40 °C and an equilibrium vapor pressure of 32 mmHg at 25 °C. Calculate the vap for isopropyl alcohol.

kJ mol-1

4. What does the term normal boiling point mean.

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

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