1. Particle Theory

2. 1.Matter is made up of tiny particles 2.Particles of matter are in constant motion 3.Particles of matter are held together by very strong electric forces 4.There are empty spaces between particles of matter 5.Each substance has unique particles different from particles from other substances 6.Temperature affects the speed of the particles

3. What do you think happens to the speed of particles when the temperature goes up?

4. Temperature and Particles It is not easy to clearly observe the smallest particles of matter. Also, within a substance some particles are moving faster than others. Scientists observe the average behavior of large groups of particles and have come up with this definition: Temperature indicates the average speed of particle motion in a substance.

5. Energy

6. What is Energy? For everyday objects we can describe position, speed, and direction of motion.

7. It is not possible to describe these observations for the very small particles that make up matter.

8. It is possible to find out how much the tiny particles can change other things. Energy is a measurement of something’s ability to cause changes or to make something else move.

9. Reflect If you were to catch a ping pong ball or a baseball, which one would have greater energy of motion?

10. Some things store more energy than others, (new versus dead batteries). Energy descriptions are useful because scientists have learned how to calculate energy values in many different situations. This allows predictions to be made about what will happen when different objects interact.

11. Hot and Cold Boiling water can move a steam engine or turn an electrical generator. Cold water cannot cause these changes. Thermal energy determines a substance’s ability to cause changes because thermal energy moves from an object at a high temp. to an object at a low temp.