1. 1.1.1 Thermodynamics
Unit 1

2. Energy Energy is the ability to do work or produce heat
Thermodynamics is the production of heat

3. Thermal Energy
Molecules and atoms that make up all substances are constantly in motion- this motion is called kinetic energy
Thermal energy is related to ‘kinetic energy’
Molecular motion increase as temperature increases?
Demo. of thermal energy-
Rub hands together

4. Thermal Energy con’t
Heat is also the flow of energy (always from a hotter substance to a colder one)
Example- hold an ice cube in your hand- what happens?
Heat from your hand is transferred to the ice cube, which then melts
Spraying water on crops to prevent frost

5. Law of Conservation of Energy
First Law:
Energy is never created nor destroyed, it only changes form
Ex- when gas is burned in your car, bond energy is converted into kinetic energy (moving pistons) and heat
Chemical reactions typically involve potential energy being converted into kinetic energy

6. Heat energy and Temperature
Heat- is the amount of kinetic energy in a sample of matter
Flows from warmer to cooler objects
Unit of heat is the Joule (J)
FYI-
one joule of energy is equal to the amount of energy used by a 100W bulb for 0.01 s
An ordinary paper match burns about 1,000 J
Another unit is the calorie (cal)

7. Temperature Temperature is a measure of the average kinetic energy
Units are in degrees celsius (oC) or in Kelvins (K)
To convert between oC and K:
oC= 273-K; K= oC+273
Assignment: converting Kelvin to celsius

8. Kinetic Energy Curves
In any substance, all of the atoms are in constant motion
However, not all molecules will have the same energy- some will be moving fast, some slow and some in between
If we were to graph this it would be a bell graph

9. Kinetic energy Curve
- for analogy

10. Something to think about:
What has more heat energy an iceberg or a cup of boiling water?
An iceberg because there are many more molecules in an iceberg than a cup of water; heat is the TOTAL kinetic energy therefore more molecules means more energy