1. Kinetic Theory of Gases Chemistry Mrs. Coyle

2. Part I- Kinetic Molecular Theory and Pressure

4. Gas Phase

5. State Variables of a Gas: describe the State of a Gas (PVT) SI Unit Pressure (P) Pascals Pa Volume (V) m 3 Temperature (T) Kelvin Amount of gas molecules mol

6. Standard Temperature and Pressure (STP) 1 atm =760mmHg (torr) = 101.3 kPa 273K =0 0 C

7. Pressure P= F A Units of Pressure: pascal, mmHg, atm 1 Pa = 1 N/m 2

8. Kinetic Molecular Theory (KMT)- Ideal Gases 1.The volume of the individual particles of a gas are negligible compared to the distances between them. 2.The particles are in constant motion. The collisions of the particles with the walls of the container cause pressure.

9. KMT Continued 3.The particles are assumed not to exert attracting or repelling forces on each other. The collisions are perfectly elastic. No kinetic energy is lost before and after the collision. 4.The average kinetic energy of a gas is directly proportional to the Kelvin temperature.

10. Simulation http://www2.biglobe.ne.jp/~norimari/scienc e/JavaApp/Mole/e-gas.htmlhttp://www2.biglobe.ne.jp/~norimari/scienc e/JavaApp/Mole/e-gas.html

11. Part II Temperature and KE Measuring Pressure: Barometer, Manometer

12. Temperature How hot – cold Average kinetic energy of molecules.

13. Temperature Scales Freezing Point of WaterBoiling Point of Water Celsius0100 Kelvin273373 Fahrenheit32212 K=273+C (absolute zero: 0 K) F=(9/5)C +32 When you increase T by one degree C, how many K do you increase by?

14. Kinetic Energy KE= ½ m v 2 v speed, m mass Example: speed of oxygen molecule at 25 o C = 443 m/s

15. Manometer- Open End P C =P B P A = Atmospheric Pressure P B =P A + P AB P AB is measured in mmHg (torr) P AB is called gauge pressure. Gas Sample

16. Manometer- Closed End “Barometer” P C =P B P A = 0 atm P B = P AB Gas Sample