1. Warm Up 3 examples of physical changes are:
3 examples of chemical changes are:

2. Temperature
Temperature is a measure of the average kinetic energy of particles of a substance.
At higher temperatures, particles move faster
At lower temperatures, particles move slower
Cooler Warmer

3. The gas particles on the right have a higher average kinetic energy than those on the left. So, the gas on the right is at a higher temperature.

4. Four scales: 0 K = 0 R: absolute zero Fahrenheit (°F) Celsius (°C)
Kelvin (°K)
Rankine (°R)
0 K = 0 R: absolute zero
All motion stops

5. Thermal Energy
Thermal energy is the total amount of kinetic energy in a substance.
Measured in Joules
thermal energy and temperature are NOT the same thing.

6. Thermal Energy

7. Heat - the movement of thermal energy
Measured in Joules
ALWAYS moves from higher to lower temperatures
Will move until objects reach thermal equilibrium (equal temps)
34o C
67o C

8. 1. On a cold day, you make some hot chocolate
1. On a cold day, you make some hot chocolate. Which way will the thermal energy move?
From the hot chocolate to the environment
From the environment to the hot chocolate

9. 2. On a hot day, you pour a glass of ice water.
Which way will the thermal energy move?
From the ice water to the environment
From the environment to the ice water

10. Average kinetic energy of particles Total kinetic energy of particles
Energy measured
Units measured
Temperature
Thermal Energy
Heat
Average kinetic energy of particles
Degrees (C, F) or K
Total kinetic energy of particles
Joules
Transferred energy
Joules

11. Thermal Expansion What is thermal expansion?
Thermal expansion - as an object is heated, that object expands.
Exception to rule: water

12. Thermal Expansion
As the temperature of roads increase or decrease, their volume expands or contracts. Expansion joints like this are placed in bridges to account for their frequent change in volume.
As the temperature in a liquid thermometer increases, its volume also increases, causing the level of the liquid to rise.
As hot air expands, it becomes less dense, allowing the hot air balloon to rise.