1. Investigation 5 - Energy Transfer 8th Grade Chemical Interactions

2. Water Mixing Review
What happened to the hot water when it was mixed with the cold water?
What happened to the cold water when it was mixed with the hot water?

3. Water Mixing Review
What happened to the kinetic energy of the particles in the hot water when the hot and cold water mixed?
What happened to the kinetic energy of the particles in the cold water when the hot and cold water mixed?

4. Water Mixing Review The hot water particles had high kinetic energy.
The cold water particles had low kinetic energy.
We mixed hot and cold water to make warm water.

5. Water Mixing Review
The average kinetic energy of the warm water particles was medium.
The kinetic energy of the hot water particles and cold water particles changed when they were mixed.

6. Tf = Th + Tc 2 Water Mixing Review
Equation for finding the average kinetic energy level:
Tf = Th + Tc 2

7. Temperature Change Heat moved from hot water to cold water.
The kinetic energy changed.
The two waters blended:
Hot + Cold = Medium.

8. Temperature Change Heat moved from hot water to cold water.
The kinetic energy changed.
The two waters blended:
Hot + Cold = Medium.

9. Energy Transfer
The movement from one place to another is called energy transfer.
Sometimes matter gets hot as a result of energy transfer.
Sometimes matter gets colder as a result of energy transfer.

10. Change of temperature is evidence of energy transfer.

11. Energy Transfer Important Idea #1:
The particles that make up matter are in constant motion. As a result, particles have high kinetic energy.
The level of kinetic energy of the particles in a sample of matter determines how hot it is.
Kinetic energy = Heat
The greater the kinetic energy of the particles in a sample of matter, the hotter it is.

12. Energy Transfer Important Idea #2:
Energy transfers as a result of particle collisions.
When fast-moving particles collides with a slow-moving article, the one that was going fast slows down, and the one that was going slow speeds up.

13. Energy transfers between particles when they collide.
Important Idea #2 Continued:
Energy transfers between particles when they collide.

14. Energy Transfer
Important Idea #2 Continued:
Energy transfer that results from collisions is called conduction.

15. Energy Transfer
Important Idea #3:
Energy always moves from higher energy (hot) to lower energy (cold). ALWAYS.

16. Energy Transfer Summary: Kinetic Energy = Heat
Energy transfers between particles when they collide.
Energy always transfers from hot to cold.

17. Energy Transfer Practice
Foss Web Multimedia:
Energy Transfer by Collision
Mixing Hot and Cold Water

18. Celsius Thermometer A thermometer is a tool measures temperature.
Temperature is the average kinetic energy of the particles of a substance.
Temperature is measured in degrees.
Celsius is one way to measure the average kinetic energy of the particles in a substance.

19. Celsius Thermometer
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