1. Heating Objects Specific Heat: the amount of energy needed to raise the temp of one gram of any particular substance up 1 0 C This is a property of a substance. If something has a high specific heat, it takes a lot more energy to raise the temperature.

2. SPECIFIC HEAT Examples: water– HIGH specific heat (a lot of heat needed to increase its temperature). Metals – LOW specific heat (not much heat needed to raise its temperature). Low specific heat – heat goes in and out QUICKLY High specific heat – heat goes in and out SLOWLY

3. Thermal Energy Heat –The transfer of thermal energy –The particles use the energy to speed up OR to break down their bonds

4. Phase Change – matter changes its form (solid, liquid, gas, plasma) Energy added or removed is responsible for the different states of matter. Matter can be made to change phase when energy is added to or taken away from a substance.

5. States of Matter Solids Liquids Gases Plasma –What is plasma? –Where is it found?

6. Thermal Energy What should happen to the temperature of ice as it melts? What should happen to the temperature of water as it boils?

7. Lets Find out….. Two of your classmates will take the temperature of ice as it is melting, then they will take the temperature of water as it boils……

8. Heating Curves (any substance)

9. Melting and Boiling Points Melting Point Temperature at which melting (or freezing) happens Boiling Point Temperature at which vaporization (or condensation) happens A physical property, unique to each material (Can be used to identify unknown substances)

10. Heating Curves

11. Thermal Energy Endothermic Processes- Thermal Energy Added –Heat is being absorbed by the substance –Melting and vaporization

12. Endothermic Phase Change Melting – phase change from a solid to a liquid when the substance absorbs heat energy. Melting Point Water 0° C. Table salt 801° C. Diamond 3700° C.

13. Endothermic Phase Changes Vaporization phase change from a liquid to a gas when the substance absorbs heat energy. Vaporization occurring at the surface of a liquid is called evaporation.

14. Sublimation – Solid to Gas Endothermic process of changing from a solid right into a gas. Solid to gas change occurs when the surface particles of a solid change directly into a gas without going through the liquid phase…

15. Exothermic Processes –Heat is being taken away from the substance –Freezing and Condensation Thermal Energy

16. Exothermic Phase Change - Condensation Gases can change phase, also in a gas to liquid phase change. A substance in the gas phase that loses heat will change to a liquid. Condensation- Phase change from a gas to liquid.

17. Condensation Water vapor in surrounding air loses heat energy when it comes in contact with the cold glass. Water vapor condenses and becomes liquid drops of water.

18. Exothermic Phase Change- Freezing Opposite of melting: Freezing- phase change from a liquid to solid. Freezing occurs when a substance loses heat energy. The freezing point of a substance is equal to the melting point!

19. Phase Change Graph

20. Deposition – Gas to a Solid Exothermic process of changing from a gas right into a solid. FROST….

21. Heat Changes Things. What happens when you heat things? Heat – things expand. Cool – things contract.

22. Why are these joints put in bridges?

23. The Verrazano-Narrows Bridge If temp changes from freezing to 90 0 F the bridge can lengthen by 2 feet!!

24. Guess where this was? When expansion joints fail…

25. States of Matter Solids Liquids Gases Plasma –What is plasma? –Where is it found?

26. Solids Key Concept: The fixed, closely packed arrangement of particles causes a solid to have a definite shape and volume (even if they are still moving a little) Your pencil is a solid. The shape and volume of your pencil will not change if you move the pencil from place to place.

27. The particles of a solid cannot move from their spot within the solid. However, the particles can move slightly back and forth in place.

28. QUESTION Imagine that the containers below both contain grape KoolAid. Which one has a higher temperature (average kinetic energy) ? Why? A B

29. What a solid looks like at particle form

30. Liquids Key Concept: Because its particles are free to move, a liquid has no definite shape. However, a liquid does have a definite volume. A liquid is a kind of matter that has a fixed volume. However, the shape of a liquid changes with the shape of its container.

31. Questions 3. What are the characteristics of a liquid? Because its particles are free to move, a liquid has no definite shape, but it does have a definite volume.

32. Water is a liquid. As you pour water from one cup to another, the shape of the water changes to match the shape of the cup. The volume of the water stays the same. The particles of a liquid are packed closely together. However, these particles can move away from their spots.

33. What a Liquid looks like at the particle level

34. Gases Key Concept: As they move, gas particles spread apart, filling all the space available. Gases do not have a definite shape nor definite volume. A gas is a kind of matter that easily changes volume and shape.

35. Air is a gas. When you blow air into a balloon, the air takes the shape of the balloon. When you let the air out of the balloon, the particles spread out into the room. Gas particles can move around freely. Gas particles can either spread apart or be squeezed together.

36. What a gas looks like at the particle level