1. Thermal Energy

2.  Matter is made of particles that are in constant random motion  The faster the particles move, the warmer an object gets

3. Kinetic Theory  This is the basis of Kinetic Theory

4. Temperature  Temperature is the measure of average kinetic energy of an object  Temperature and energy are directly related  The more kinetic energy, the higher the temperature  The more potential energy, the lower the temperature

5. Temperature  The standard unit for temperature is Kelvins (K)  We also use Celcius and Farenheit  Kelvin -273 = ˚C

6. Why does the ice melt?

7. Thermal Energy  The total of the Kinetic Energy and Potential Energy of all particles in an object.  Thermal energy and temperature are directly related  Thermal energy and mass are directly related

8. Thermal Energy and Mass

9. Heat  Thermal energy that flows from something at a higher temperture to something at a lower temperature is called heat  Heat is measured in Joules (J)  An example is when you get up from a chair and it is warm to the touch.  In science, ther is no cold, only absence of heat

11. Specific Heat  Specific heat is the amount of heat needed to raise 1 kg of a substance 1 ˚C  It is measured in J/kg ˚C

12. Substance Specific Heat Capacity at 25 o C in J/g o C H 2 gas14.267 He gas5.300 H 2 O (l) 4.184 ethyl alcohol2.460 air1.020 magnesium1.020 nickel0.440 zinc0.39 copper0.385 brass0.380 sand0.290 silver0.240 tin0.21 lead0.160 mercury0.14 gold0.129

13. Specific Heat  Water has a very high specific heat.  It is good as a coolant in radiators

14. Formula for Change in Thermal Energy  The formula for thc change in thermal energy is Q = mCΔT  Q – the change in thermal energy  M – mass of the object  C – specific heat of the substance  ΔT – change in temperature (T final – T initial)