1. Temperature and Thermal Energy
Chapter 9 Section 1
Temperature and Thermal Energy

2. Kinetic Theory of Matter
Describes the motion of the particles
Matter is composed of particles that are atoms, molecules or ions
These particles are always in random motion
Moving at different speeds in all directions
Because particles are in motion, they have kinetic energy.

3. Temperature Measures the average kinetic energy of its particles
As the movement increases, the temperature increases

4. Temperature Scales Kelvin Celsius Fahrenheit SI unit for temperature
Subtract 273 from Kelvin to get Celsius
Fahrenheit

5. Thermal Energy The sum of potential and kinetic energy
Particles have potential energy because molecules exert attractive forces on each other
As particles get further apart, the potential energy increases
The thermal energy of an object changes when its temperature changes

6. Heat
Heat is the thermal energy that flows from something at a higher temperature to something at a lower temperature

7. Specific Heat
Specific heat is the amount of thermal energy needed to raise the temperature of 1 kg of some material by 1 Degree C
Different materials have different specific heats

8. Measuring Specific Heat
Specific heat of a material can be measured using a calorimeter
An instrument for measuring the amount of heat released or absorbed in physical and chemical processes.

9. Chapter 9 Section 2
States of Matter

10. Five States of Matter
Solid
Liquid
Gas
Plasma
Bose-Einstein Condensate

11. Solid Particles are packed closely together
Particles constantly vibrating in place
Attraction between particles are strong
Solids have fixed volume and shape

12. Liquid State
Attractive force between particles are weaker than in a solid, but are strong enough to cause particles to cling together
Particles can slide past each other
Liquids flow and take the shape of a container
Liquids have a definite volume but not a definite shape

13. Gas State Particles are much farther apart than in a solid or liquid
Attractive forces are weak because the particles are far apart
Gases do not have a definite shape or volume
Gas containers contain mostly empty space
Gas particles spread until they are distributed evenly
Diffusion

14. Table Activity
Each table will be responsible for acting like a solid, liquid and gas.
Solids- group stands close together
Each person vibrating slightly
Liquids – Molecules flow around each other
Gases – Molecules bounce off each other quickly

15. Plasma State Most common state of matter in the universe
Matter consisting of positively and negatively charged particles
Does not have a definite shape or volume
Results from collisions between particles moving at such high speeds that electrons are knocked from the atoms
Examples are lightning bolts, neon and fluorescent tubes, auroras

16. Bose-Einstein Condensate
Observed in a lab in 1995
Near absolute zero, atoms meld together to form a super-atom

18. Changing States Adding thermal energy causes a phase change Melting
Solid to Liquid
Amount of energy required to change substance from solid to liquid is heat of fusion
Freezing
Liquid to Solid

19. Changing States Vaporization Boiling Condensation Liquid to Gas
Does not need to occur through whole liquid
Boiling
Throughout the liquid
Specific temperature makes the liquid boil
Condensation
Gas changes to liquid

20. Heating Curve of a Substance

21. Transferring Thermal Energy
Chapter 9 Section 3
Transferring Thermal Energy

22. Heat transfer demo

23. Ways to transfer Thermal Energy
Heat moves from a warmer object to a cooler object
Thermal Energy moves from one object to another
Conduction
Convection
Radiation

24. Conduction Transfer of energy between colliding particles
Faster moving atoms collide with slower moving particles
As these collisions continue, energy is transferred
Is transferred by collisions between particles, not by movement of matter
Different materials conduct better than others
Best thermal conductors are metals
Gases are poorer conductors than solids or liquids

25. Convection
Transfer of thermal energy in a fluid by the movement of fluid from place to place
As particles move faster, they tend to be further apart
This causes fluid to expand
Volume increases, but mass stays the same
Water is an exception

26. Convection Currents

27. Radiation Transfer of energy by electromagnetic waves
Can travel even when there is no matter present
When radiation strikes a material, it can be absorbed, reflected, or transmitted through the material

28. Thermal Insulators A material in which thermal energy moves slowly
Gases are usually the best thermal insulators because they keep convection currents from forming

30. Popcorn Example
Chapter 9 word document

31. Chapter 9 Section 4
Using Thermal Energy

33. Heating Systems Forced Air Systems Radiator Systems
Fuel is burned in furnace and heats air
Fan blows heated air
Radiator Systems
Closed metal container that contains water or steam
Water heated and sent through pipes
Closed system
Electric Heating Systems
Converts electrical energy to thermal energy

34. Thermodynamics First Law of Thermodynamics
Increase in thermal energy of a system equals the work done on a system plus the thermal energy transferred to the system

35. Second Law of Thermodynamics
It is impossible for thermal energy to flow from a cool object to a warmer object unless work is done

36. Closed vs. Open System Open System Closed System
Work is done across a boundary
Closed System
No work done across a boundary and no outside work done

37. Heat Engine Device that converts thermal energy into work Cars Engine
Only about 25% is converted into work
Internal Combustion Engine
Fuel burned in engine chambers
Cylinder moves a piston up and down