1. CHAPTER 6 THERMAL ENERGY

2. PS 7 a-c 1. I can illustrate and explain the addition and subtraction of heat on the motion of molecules. 2. I can distinguish between heat and temperature. 3. I can compare/contrast Celsius and Kelvin temperature scales and describe absolute zero 4. I can analyze a time/temperature graph of a phase change experiment to determine the temperature at which the phase change occurs. 5. I can compare/contrast conduction, convection, and radiation and provide and explain common examples. 6. I can explain how the principles of heat transfer applies to heat engines, thermostats, refrigerators, and heat pumps

3. SECTION 1: TEMPERATURE AND HEAT Temperature: how hot or cold something seems to be Matter is in constant motion, which is kinetic energy Temperature is the average kinetic energy of a substance The faster molecules move, the higher the temperature Measured in Celsius or Kelvin using a thermometer

4. TEMPERATURE SCALES CELSIUS (°C) °C = K - 273 KELVIN (K) K = °C + 273 Examples: 20 °C = ? K 20 K = ? °C K = 20 + 273 °C = 20 - 273 K = 293 K °C = -253 °C Water freezes at 0°C or 273 K Water boils at 100°C or 373 K

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7. Thermal energy: the total kinetic and potential energy in a substance Heat: thermal energy that flows from hot to cold

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9. Absolute zero: The coldest possible temperature The temperature when an object has no kinetic energy, particles in matter are not moving Zero Kelvin or -273°C

10. SECTION 2: TRANSFERRING THERMAL ENERGY Conduction: transfer of thermal energy by two objects touching Heat conductors: materials that transfer heat easily Examples: metals such as silver, copper, aluminum

11. Convection: transfer of thermal energy in a fluid (liquid or gas) by the movement of particles Radiation: transfer of thermal energy by electromagnetic waves Radiation Sun’s heat Also called radiant energy Does not require a medium

12. Insulator: a material that does not allow heat to flow through easily Examples: wood, plastic, fiberglass, wool, and down

13. SECTION 3: USING HEAT Heating systems: Forced-air system: a fan blows warm air throughout a room Radiator system: hot water or steam is transferred to the surrounding air Electric heat: heated coils heat the air

14. Using heat to do work: Heat engine: converts heat energy into mechanical energy Heat movers: Removes thermal energy from one location and transfers it to another Examples: refrigerator, air conditioner, heat pump

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