Vapor Procedure Lab Report
Experiment :12 Vapor Pressure and the Heat of Vaporization
Nicole Petersen
TA: Ryan Dixon
4/16/2013
Purpose: Use experimental techniques to record temperature and volume data for known and unknown compounds. The liquid and gas are going to be at equilibrium. We will also determine the boiling point for the known and unknown. Then use a graph to calculate the slope and then use Clasius- Clapeyron equation to find the heat vaporization.
Procedure: Refer to pages 155-167 of Chemistry 1210 General Chemistry Laboratory Manual Hayden- McNeil Publishing Inc. 2012-2013
Report Sheet: See attached report sheet and graphs.
Sample Calculations:
1/t= 35 C +273 K = 1/308 =0.0325 1/K
Ps= Pb (1- Vr/V * T/Tr)= 746(1-5/8*308.15/343.15)=325.3
= 3.3 x 10 ^ 2 mmHg ( converted temp to kelvins)
Hvap= -(slope) X R. R constant=8.315J mol -1 K-1 Hvap=-(-5337.8 x 8.315)= 44383.8
Graphs:
Methanol
Ethanol
Propanol
Unknown
Al the graphs combined:
Conclusion: In this lab we learned how to convert temp in Celsius to kelvin to get inverse kelvin and we also learned how to get Ps which is the pressure of the sample as well as the natural log of the sample. During the lab we had to clean all of our equipment before starting and then we set up our experiment with a hot water bath using a Bunsen burner wire gauze. We used a syringe with a needle to put our known and unknown compound in the 30 mL syringe. We each only received one of the known compounds and exchanged information to get the data needed for the other two compounds. Doing so saved a lot of time. We looked up the boiling points for our known compounds however for our unknown we actually had to find it. We found it by adding unknown sample to a test tube and once a steady amount of bubbles were observed at the open end then that was considered the boiling point. This lab was straightforward and pretty easy to follow. We took the temperature and the volume when it reached certain points. It was fun and I enjoyed finding the boiling point.
Nicole Petersen
TA: Ryan Dixon
4/16/2013
Purpose: Use experimental techniques to record temperature and volume data for known and unknown compounds. The liquid and gas are going to be at equilibrium. We will also determine the boiling point for the known and unknown. Then use a graph to calculate the slope and then use Clasius- Clapeyron equation to find the heat vaporization.
Procedure: Refer to pages 155-167 of Chemistry 1210 General Chemistry Laboratory Manual Hayden- McNeil Publishing Inc. 2012-2013
Report Sheet: See attached report sheet and graphs.
Sample Calculations:
1/t= 35 C +273 K = 1/308 =0.0325 1/K
Ps= Pb (1- Vr/V * T/Tr)= 746(1-5/8*308.15/343.15)=325.3
= 3.3 x 10 ^ 2 mmHg ( converted temp to kelvins)
Hvap= -(slope) X R. R constant=8.315J mol -1 K-1 Hvap=-(-5337.8 x 8.315)= 44383.8
Graphs:
Methanol
Ethanol
Propanol
Unknown
Al the graphs combined:
Conclusion: In this lab we learned how to convert temp in Celsius to kelvin to get inverse kelvin and we also learned how to get Ps which is the pressure of the sample as well as the natural log of the sample. During the lab we had to clean all of our equipment before starting and then we set up our experiment with a hot water bath using a Bunsen burner wire gauze. We used a syringe with a needle to put our known and unknown compound in the 30 mL syringe. We each only received one of the known compounds and exchanged information to get the data needed for the other two compounds. Doing so saved a lot of time. We looked up the boiling points for our known compounds however for our unknown we actually had to find it. We found it by adding unknown sample to a test tube and once a steady amount of bubbles were observed at the open end then that was considered the boiling point. This lab was straightforward and pretty easy to follow. We took the temperature and the volume when it reached certain points. It was fun and I enjoyed finding the boiling point.