1. Aim: What are the States of Matter

3. Nature of Gases Gases: No definite shape or volume
Particles are very far apart and move all over
Total disorder- particles move in all directions

4. Gas Pressure
Gas particles exert pressure when they collide with walls of the container they are in.

5. Atmospheric pressure
Atmospheric pressure results from the collisions of atoms and molecules in air with objects.
SI unit for pressure is the pascal (Pa).
Other units are atmosphere (atm) and millimeters of mercury (mm Hg).
Standard pressure is1 atm = 760 mm Hg = kPa

6. Atmospheric pressure
Atmospheric pressure is greater at sea level.

7. Balloon Suction Demo Answer the following questions during the demo:
1. What is air?
2. What is air pressure?
3. What do you think happens when air is heated up?
4. At what point do you think the air pressure in the flask decreased?
5. How can we get the balloon out of the flask?

8. Answers to demo
1. What is air? Air is the mix of gases in our atmosphere.
2. What is air pressure? Air pressure is the pressing, forcing, and moving of air as it interacts with things around it.
3. What happens when air is heated up? When air gets warmer, it expands and takes up more space.
4. At what stage do you think the air pressure in the flask was reduced? As the lit paper extinguished and the air began to cool.
5. How can we get the balloon out of the flask? Heating the flask…anything to increase the pressure in the flask again.

9. Kinetic Energy and Temperature
What is energy?
The capacity to do work or produce heat
What is Kinetic Energy (K.E.)?
The energy an object has because of its motion.

10. Kinetic Energy and Temperature
Temperature is a measurement of the average kinetic energy of atoms or molecules.

11. Kelvin Temperature Scale (table T)
1. K = oC
2. oC = K
3. 0 K = absolute zero
Standard temperature = 0 oC = 273 K

12. Nature of Liquids Liquids have:
Definite volume and take the shape of the container
Particles are still close together and move while touching each other
No regular pattern or arrangement of particles.

13. Evaporation
Evaporation is when liquid changes into gas.

14. Nature of Solids Solids have: Definite shape and volume
Particles are close together in fixed positions, vibrate but do not move.
Crystalline structure

15. Crystal Structure
Crystals have particles arranged in a regular geometric pattern

16. Allotropes
Allotropes are two or more molecular forms of the same elements in the same physical state.
Allotropes have different properties because their structures are different.

17. Examples of Allotropes
Two allotropes of oxygen (dioxygen, O2, and ozone, O3), can both exist in the solid, liquid and gaseous states.
Coal and diamonds are allotropes of carbon

18. Changes of State Gas  liquid = condensation
Liquid  gas = evaporation
Solid  liquid = melting
Liquid  solid = freezing
Gas  solid = deposition
Solid  gas = sublimation

19. Summary
1. Describe the behavior of particles in the solid, liquid, and gas phase.
2. Sketch how the particles would look like in each phase.