1. An Introduction to Chemistry

2. What Is Matter
 The Ancient Greeks knew…
1. Matter has mass
2. Matter takes up space
 They studied…
 Physical and Chemical properties
 They used logic to hypothesize that…
1. All matter is made up of microscopic particles
2. Each pure substance has its own unique type of particle
 But, they did not have the technology to prove their hypothesis.

3. Today We Know
 The Ancient Greeks were right!
1. All matter is made up of microscopic particles
2. Each pure substance has its own unique type of
particle
 In Addition we know…
1. The particles are always moving!
2. Particles are moving slowly in a solid.
3. Particles are moving quickly in a gas.
 Temperature is a measure of how fast particles are moving!

4. Particle Theory of Matter
1. All matter is made of extremely tiny particles
2. All pure substances are made of their own
kind of particle
3. All particles are moving.
4. Particles at higher temperatures move faster
than those at lower temperatures.
5. Particles are attracted to each other.

5. Three States of Matter
 Matter is usually found in one of three states:
 Solid – Particles are close together
 Liquid – Particles are farther apart
 Gas – Particles are very far apart
 Note: The particles are the same in each state!
 They are just moving differently
 They just have a different temperature
 Also: Additional states are possible but are less common.
(i.e. Plasma)

6. States of Matter

7. Changes of State

8. Practice
 Particle Theory Worksheet
 Journaling:
You are invited to 3 parties on the same night. The
invites come from solid particles, liquid particles or gas
particles. Which party would you go to? Explain your
thinking.