1. SECTION 1 PROPERTIES OF GASES Chapter 12 Gases

2. What are the three states of matters? List 3 properties of gases. List 3 different names of gases. Identify them as elements, compounds, or mixtures.

3. Properties of Gases Gases have unique properties because of large distance between particles

4. Compared to Solids and Liquids SolidLiquid

5. The distance between particles of a substance is referred to as intermolecular distance

6. Gases are considered Fluids Fluid – any substance that can flow Fluid describes liquids and gases

7. Gas particles can flow because of large intermolecular distances

8. Gases have Low Density Remember density = mass/volume Because of large intermolecular distances, most of the volume of a gas is empty space

9. Gases are Highly Compressible Syringe demonstration

10. Gases Completely Fill a Container

11. The gas will continue to fill side A until there are the same amount of particles on both sides

12. Gas Pressure Gases are all around us Earth’s atmosphere is filled mainly with nitrogen and oxygen

13. Gases have Mass Because they have mass, they have weight Earth’s gravity pulls particles downwards towards its center This is often referred to as air pressure

14. Ears Popping When flying in an airplane or driving up a high mountain sometimes your ears “pop” This popping happens because the density of the air changes when you change altitudes Less dense air exerts less pressure. Your ears pop when the air inside your ears changes to the same pressure as the outside air

15. Measuring Pressure Pressure = Force/Area = Newton/Meter 2 Pascal, Pa is the standard unit for pressure 1 Pa = 1 N / m 2

16. https://www.youtube.com/watch?v=QeAp3CuGjk8

17. Standard Temperature and Pressure When performing experiments with gases, it is very important to consider pressure and temperature Scientists have set up a standard temperature and pressure (STP) which is equal to 0 o C and 1 atm

18. Kinetic Molecular Theory This states that gas particles are in constant rapid, random motion. Also states that the particles of a gas are very far apart relative to their size.

19. Gas particles in constant motion collide with each other and with the walls of their container. Pressure exerted by a gas is a result of collisions of the molecules against the walls of the container.