1. gases

2. Properties of gases Gases have no definite shape or volume Particles move rapidly in all directions Molecules are in constant motion and molecules frequently collide with one another Gases are compressible Gases have low densities because molecules are far apart Gases are fluids

3. Who is Boyle? The volume of a gas increases as the pressure decreases if the temperature does not change http://www.youtube.com/watch?v= J_I8Y- i4Axc&safety_mode=true&persist_ safety_mode=1

4. Boyle’s law Formula: P 1 V 1 =P 2 V 2 P=pressure V=volume

5. example The gas in a balloon has a volume of 7.5 L at 100 kPa. The balloon is released into the atmosphere, and the gas expands to a volume of 11 L. Assuming a constant temperature, what is the pressure on the balloon at the new volume?

6. Set up the problem: V 1 = 7.5 L P 1 = 100 kPa V 2 = 11 L P 2 =unknown

7. Write the equation for Boyle’s law rearranging the equation to solve for P 2. P 1 V 1 =P 2 V 2 P 2= P 1 V 1 / V 2

8. Insert the known values for the equation and solve P 2 = (100 pKa) (7.5 L) / 11 L P 2 = 68 kPa

9. Charle’s Law In a fixed amount of gas and constant pressure, the V of a gas increases as the T increases and the V of a gas decreases as the T decreases. http://www.youtube.com/watch?v=UiFScneyvwQ&feature= related&safety_mode=true&persist_safety_mode=1

10. Gay-Lussac’s law States that the pressure of a gas increases as the temperature increases if the volume does not change

11. Tomorrow: You will creating brochures

12. Worksheet will be handed out in class This must be stamped!