1. Gas Laws

2. 2 Kinetic – Molecular Theory 1. Particle size – Gases contain _________________________ ______________________________________ – Because so small and far apart there is no repulsive nor attractive forces among them

3. 2. Particle motion – Gas particles are _____________________________________ – Particles move in straight lines until they collide with something – Elastic collision = NO kinetic energy (KE) lost KE can be transferred ________________________________________

4. 3. Particle Energy – Mass and velocity determine KE ______________________ – Velocity is speed & direction – All gas particles do NOT have the same velocity so do NOT have same KE – KE and temperature are related Temp is _________________________________________ _________________________________________________ At a given temp, all gases have same average KE

5. 5 Dalton’s Law of Partial Pressure Total pressure of gas mixture = _________________________________ P total = P 1 + P 2 + P 3 + …..

6. 6 Example Dalton’s Law A mixture of oxygen, carbon dioxide (pressure = 0.70 atm) and nitrogen (pressure = 0.12 atm) has a total pressure of 0.97 atm. What is the pressure of the oxygen? P total = P O2 + P CO2 + P N2

7. Boyle’s Law Formula: Units Volume: Units Pressure: Example A balloon has a volume of 2.6 L and a pressure of 0.997 atm. If the volume increases to 4.6 L, what is the new pressure? Graph: directly or indirectly proportional?

8. 8 Conversion for Pressure ____ atm = ____ mmHg = ____ torr = ____ kPa

9. 9 Practice To convert between two units, make unit multipliers: How many kPa is 0.75 atm?

10. Charles’ Law Formula: Units T  Kelvin used – Conversion to K Example A balloon was moved from a temperature of 25 degrees Celsius to 45 degrees Celsius. If the initial volume was 125 ml, what is the final volume? Graph

11. Gay-Lussac’s Law Formula: Example A canister has a pressure of 1.23 atm at a temperature of 29 degrees Celsius. If the temperature is 400K, what is the new pressure in torr? Graph

12. Avogadro's Principle Conversion factor 1 mole = __________ Example For the reaction 2 H 2(g) + O 2(g)  2 H 2 O (g), how many liters of water can be made from 5 L of oxygen gas and an excess of hydrogen at STP?

13. Combined Gas Law Formula Example I have an unknown volume of gas at a pressure of 0.5 atm and a temperature of 325 K. If I raise the pressure to 1.2 atm, decrease the temperature to 320 K, and measure the final volume to be 48 liters, what was the initial volume of the gas?

14. Ideal Gas Law Formula: ________________ R = 0.0821 L atm/K mol Example If 5 moles of a gas at a pressure of 5.4 atmospheres have a volume of 120 liters, what is the temperature in Celsius?

15. How do I know? When moles are present? – Use ___________________________ When NO moles are mentioned? – Use ___________________________ Only plug in for things you have; all other items, delete.

16. 16 Phase Diagram for Water