1. 1. Label each of the particle diagrams below with the state of matter each picture represents 2. What are the differences between an atom, an element and a compound? 123

2. Discussion Atoms closely packed together very little movement A little space between atoms Atoms flow over each other A lot of space between atoms Atoms move quickly SOLIDLIQUIDGAS

3. Do Now Discussion What is the difference between an atom, an element and a compound? An atom is the smallest piece of matter. An element is one type of atom A compound is made of more than one element bound together

4. Chapter 12.1: Gases and Kinetic Molecular Theory 3/30/11 Notes

5. Kinetic Molecular Theory (KMT) What does it mean?  Kinetic = to move  Molecular = molecules/atoms  It means Moving molecules! solid liquid gas

6. Why is KMT important? Kinetic-molecular theory explains the different properties of solids, liquids, and gases (states of matter) describes the behavior of matter in terms of particles in motion.

7. KMT Postulates (Rules) Gases consist of small particles separated by empty space. Gas particles are too far apart to experience significant attractive or repulsive forces. Gas particles move in straight lines until they collide with something else Kinetic energy of a particle depends on mass (m) and velocity (v) KE = ½mv 2

8. Kinetic Energy, mass and velocity KE v v m How are KE, m and v related?

9. Why are gases important? Methane gas – an inexpensive fuel that we use to heat our homes and power our kitchen stoves Nitrogen gas – generated to inflate air bags in a car accident 2 NaN 3  2 Na + 3 N 2 Oxygen – So we can breathe/live…kind of important.

10. Properties of Gases There is a lot of “free” space between particles in a gas. There is a lot of “free” space between particles in a gas. Gases can be compressed (reduce the space between particles) Gases can be compressed (reduce the space between particles) compression

11. Gases can be expanded infinitely (increase the space between particles) Gases can be expanded infinitely (increase the space between particles) Gases fill containers uniformly and completely. Gases fill containers uniformly and completely.

12. Gases diffuse and mix rapidly. Gases diffuse and mix rapidly. Diffusion: the movement of one material through another Diffusion: the movement of one material through another  Example: food coloring in water  Gas Example: air freshener

13. Assignment Choose any three bullet points on your notes, copy them onto the back of your paper, then draw pictures showing what they mean