1. Pressure Law

2. Procedure: 1. Air trapped in a flask is heated in a water bath.
2. Use the thermometer and Bourdon gauge to measure the temperature and the pressure of the air.
3. Take about several readings with different temperature.

3. Result

4. Graph Plotting Pressure / kPa 130 120 110 100 90 Temp. / C 20 40 60 80

5. Pressure - Temperature
What is this relation?

6. Result The graph of pressure against temperature is a straight line.
Is Pressure directly proportional to Temp.?
Pressure
Temperature

7. Is P directly proportional to T?
Pressure
Temperature / C
P = T + constant (y-intercept)

8. Is P directly proportional to T?
Pressure
Temperature

9. Is P directly proportional to T?
Pressure
Temperature

10. Is P directly proportional to T?
Pressure
Temperature

11. Is P directly proportional to T?
Pressure
Temperature
-273C

12. Is P directly proportional to T?
Pressure
Temperature
-273C

13. Is P directly proportional to T?
Pressure
Temperature
-273C
0 K
273K
P is directly proportional to T!

14. Is P directly proportional to T?
Kelvin Scale
Pressure
K = C
Temperature
0 K
273K
P is directly proportional to T!

15. Result

16. Result

17. Graph Plotting

18. Conclusion P  T P/T = constant P1 /T1 = P2/T2 Pressure Law
Pressure of a fixed mass of gas at constant volume is directly proportional to its Kelvin temperature.