1. HEAT the transfer of thermal energy from hot objects to cold objects through collision of particles Units=Joules

2. Thermal Energy the total kinetic and potential energy of an object Units = Joules

3. Temperature a measure of the average molecular motion of a substance (if temp is high-KE is high)

4. Energy Transfer- (3 ways) 1. Conduction – transfer of thermal energy by direct molecular contact with no transfer of matter (materials need to touch) Ex: Your hand will get burnt when you touch a hot burner

5. 2. Convection – transfer of thermal energy by the flowing action within a liquid or a gas. Ex: A furnace circulates warm air to the colder areas of the room

6. 3. Radiation – transfer of energy through space in the form of waves. Ex: Thermal energy from the sun travels through space to the earth

7. 1.Energy is conserved in a system. 2.Heat can only flow from cold objects to hot objects when work is done on the system. 3.Absolute zero can never be reached. Three Laws of Thermodynamics

8. Chemical Reactions and Heat Exothermic Reactions- reactions that release heat energy when chemical bonds are broken. Ex.) burning wood, hand warmers

9. Endothermic- reactions that absorb heat Ex) cold pack

10. When a substance is heated-  The motion of the particles increase  The number of collisions increase  The volume of the substance increases