Methods:

Set Up

1. Set a 1500-mL beaker, 3/4 full with water, on the hot plate with magnetic stirrer and gently place a stirring bar in the beaker.
2. Use the ring stand and utility clamp to mount a 250-mL Erlenmeyer flask in the water bath so it is immersed as much as possible without allowing water to enter in the top.
3. Turn on the hot plate. Heat the water bath until the temperature is about 80 Degrees Celsius.
4. Start a new experiment on the data collection system.
5. Place the barbed connector of the absolute pressure sensor tightly into the rubber stopper and connect it to the pressure port of the sensor with a piece of tubing.
6. Insert the temperature sensor into the other hole in the rubber stopper.  If necessary, add a drop of glycerin.
7. Connect the absolute pressure sensor to the data collection system using a sensor extension cable.
8. Place the stopper into the Erlenmeyer flask to test for a tight fit.
9. Remove the stopper.
10. Transfer 50mL of ethanol into the Erlenmeyer flask in the water bath.

Collect Data

1. Once the ethanol starts to boil, allow a few minutes for the ethanol fumes to fill the flask.
2. Remove the flask from the water bath and immediately insert the stopper tightly.
3. Start recording data.
4. Continue the data collection until the temperature drops to about 30 degrees Celsius.
5. Stop recording data.
6. Discard the ethanol as instructed by your teacher and rinse the flask.
7. Repeat the procedure with a 60 Degrees Celsius bath and 50 mL of acetone. Allow the flask to cool to about 25 Degrees Celsius.
8. Display both data runs, and clean up according to teacher's instructions.

Equipment:

• Data Collection system
• stainless steel temperature sensor
• Absolute pressure sensor with quick-release connectors and plastic tubing
• Sensor extension cable
• Beaker, 1500-mL
• Beaker, 50-mL
• Erlenmeyer flask, 250-mL
• Graduated cylinder, 50-mL
• Hot plate with magnetic stirrer and stirring bar
• Clamp, utility
• Ring stand
• 100% Ethanol, 50mL
• Acetone, 50mL
• Rubber stopper, 2-hole
• Glycerin, 2 drops
• Water, 1200 mL