1. Lesson 12.1 Gases

2. Density density pepsi vs diet pepsi 3.5 mindensity pepsi vs diet pepsi volume of a marble density animation

3. What are the main physical properties of gases? Gases assume the volume and shape of the container. Gases are most compressible of states of matter. Gases will mix evenly and completely when confined to same container. Gases have much lower densities than liquids and solids.

4. List the Gases Periodic Table in back of textbook Why diatomic?

5. Noble Gases Single atoms Complete outer valance shell Octet rule is satisfied

6. Kinetic Molecular Theory Gases have similar physical properties Little variation in behavior Kinetic = Greek word “to move” Particles in motion Particles are small –Lots of empty space –No significant attraction or repulsion forces Constant random motion

7. Kinetic Energy = ½ mv 2 Molecules travel in a straight line Hit a wall or another molecule then Energy is transferred – no energy is lost m is mass v is velocity (speed and direction)

8. Compression and Expansion

9. Diffusion and Effusion Diffusion – smell cooking throughout the house Effusion – gas escapes from a small hole different rates depends on size Smaller particles travel faster

10. Diffusion Ratio NH 3 or HCl Back to molar mass! NH 3 36.5 g/mol and HCl 17.0 g/mol

11. Find Diffusion Ratio N 2 and Ne CO and CO 2

12. Pressure Think about it Walk on deep snow with boots, snow shoes, skis. Which sink the most? Why?

13. Pressure = force / unit of area The pressure in car or bicycle tires is measured in pounds per square inches. Car tires 26-30 lb/sq.in. Bicycle tires 40-60/sq.in.

14. Who will wear out the carpet first? 125 lbs woman wearing high heels? Or, same woman wearing flats? Why?

15. Barometer or Manometer Instruments that measure pressure

16. Units of Measure

17. Dalton’s Law Partial Pressure P total = P 1 + P 2 + P 3 +... + P n O 2 + CO 2 + N 2 P CO 2 = 0.70 P N 2 = 0.12 P total = 0.97 atm Find P O 2 = 0.97 – 0.70 – 0.12 = 0.15 atm

18. Textbook page 409 # 4,5,6

19. p. 409 # 4,5,6 4.P H2 = 161 mmHg 5.P total = 13.78 kPa 6.P CO2 = 10.2 kPa

20. Explain how a person can break a board, like in Karate?