Exp. E-1A
A. Obtain a pressure-measuring device as indicated by your lab instructor. Obtain a 60 mL syringe, fill it with air, and connect the syringe to the gas-measuring device as indicated in the figure. Test your apparatus for gas leaks. If you can't eliminate all leaks, see your lab instructor.
B. If necessary, calibrate your gas-measuring device as indicated by your lab instructor. Fill your syringe to the largest volume mark on the syringe and reconnect to the gas-measuring device. What is the pressure of the trapped air in the syringe? Explain.
-The pressure of the trapped air in syringe is 0.01 bar or 0.00987 atm. The pressure of trapped gas is equal to the pressure of the atmosphere because it is measured relative to the atmospheric pressure.
C. Depress the plunger of the syringe and describe the system. Is the pressure of the trapped air greater or less than the atmospheric pressure? Explain.
- The pressure of the trapped air is higher than the atmospheric pressure. Since the gas are being compressed inside the syringe, and reducing its volume. This will caused the molecules to hit the container more often since there isn't much space. The frequent collision between the gas molecules and the container causes a rise in pressure.
D. Release the plunger of the syringe. Adjust the plunger to the 60mL mark. Record the pressure reading of the trapped air in the following table.
Atmospheric pressure = 732 torr at 9:00 A.M, November 6, 2012.
Pressure (bar)
Pressure (atm)
Volume (mL)
0.04
0.0395
60
0.15
0.1480
54
0.29
0.2863
48
0.46
0.4540
42
0.68
0.6713
36
1.00
1.0130
30
1.45
1.4314
24
2.13
2.1027
18
2.52
2.4877
12
2.80
2.7640
6
II. Data Analysis
A. If necessary, calculate the total pressure of the trapped air for each reading and record it in the following table. Show how you calculate this pressure for your first reading in the space below.
Total Pressure = Pressure