1. Investigating Heat
Investigation 1

2. Vocabulary (Lab Learner p.1)
Celsius-basic unit in the metric system for measuring temperature. Degrees Celsius are represented as “˚C”.
Degrees-equal divisions of units of temperature
Fahrenheit-Basic unit in the English system for measuring temperature. Degrees Fahrenheit are represented as “˚F”.
Heat-The energy transferred from one molecule to another because of a difference in kinetic energy between the two molecules.
Kinetic energy-the energy of motion

3. Vocabulary continued…
Molecule-a particle of matter.
Temperature-a measure of the kinetic energy of molecules.
Thermometer-a scientific tool that measures temperature in degrees Celsius (˚C) and degrees Fahrenheit (˚F).

4. HEAT Heat is energy, not matter.
Heat is the difference in energy between molecules of higher kinetic energy and molecules of lower kinetic energy.
Solids: lowest kinetic energy, molecules closer together
Liquids: faster than solids, molecules further apart
Gasses: molecules move quickest, molecules furthest apart

5. Kinetic energy of molecules
As the molecules move faster, they move further apart. As this happens, they change the state they are in.

6. Heat
Heat can be transferred through conduction, convection, and radiation.

7. How is heat energy transferred?
Conduction: The direct transfer of heat between objects that touch.
Convection: The transfer of heat as a result of the mixing of a liquid or a gas. Example: the boiling water in a pot transfers the heat to the egg in it.
Radiation: The transfer of heat energy by electromagnetic waves. (kind of like sound waves and light waves travel through the air) Example: a toaster.

8. How a thermometer works:
A thermometer usually contains liquid alcohol, colored to be easily seen.
When the thermometer is placed in a substance, kinetic energy is transferred from the molecules of higher kinetic energy to molecules of lower kinetic energy.
The alcohol will then expand (if the substance is warmer) as the molecules of alcohol move faster causing the temperature to rise.

9. Using a thermometer (continued)
If the substance is a lower temperature than the alcohol in the thermometer, the kinetic energy of the alcohol in the thermometer will be transferred to the substance.
This will cause the molecules of the alcohol in the thermometer to move closer together as they slow down, and the level of the liquid will appear to drop.

10. Common Temperature Readings
The boiling point of water is 100˚C, or 212˚F.
The freezing point of water is 0˚C, or 32˚F.
The average human body temperature is 37˚C or 98.6˚F.

11. Effect of Water Temperature on Time Needed for Food Coloring to Spread
100 95 90 85 80 75 70 65
TIME
WATER TEMPERATURE

12. Page 9
8. As the temperature of the water increases, the kinetic energy of the molecules ______________. 9.When the balloon inflated showed kinetic energy. When the food coloring spread through the water, we saw kinetic energy.