Topic : Chemistry

1. Topic: Chemistry Aim: Explain the different types of phase changes and the energy changes involved. Do Now: Write the aim on today’s notes sheet. Tape today’s notes sheet on the back of yesterday’s notes. HW: Properties Reading due Monday!

2. SOLID LIQUID GAS

3. Gas Let’s summarize… Identify the phase being described (solid, liquid or gas): • No definite shape or volume. • Takes the shape of the container it is in and has a definite volume. • Made up of high energy atoms. • Atoms are tightly packed together. • Molecules are cohesive. • Has a definite shape and volume. • Takes the shape of a closed container. Liquid Gas Solid Liquid Solid Gas

4. Observe the phase change diagram. Identify the events that can occur to cause a phase change. HEAT IS RELEASED OR HEAT IS ABSORBED

5. Melting Substance absorbs heat energy

6. Substance GAINS energy

7. Melting • S  L • Solid ABSORBS heat energy Substance absorbs heat energy

8. Melting points of different substances • Iron: 1536ºC • Gold: 1063ºC • Glucose: 150ºC • Urea: 132-134ºC

9. Identify the phase change represented in the photographs below.

10. Substance loses heat energy LIQUID SOLID

11. Freezing • L  S • Liquid RELEASESheat energy Substance loses heat energy

12. Identify the process occurring in the animation.

14. Substance ABSORBSenergy GAS LIQUID

15. Vaporization • L  G • Liquid ABSORBS heat energy • Evaporation: occurs on surface of liquid GAS Liquid absorbs heat energy LIQUID

16. Boiling points of different substances • Alcohol (Ethanol): 79ºC • Iodine: 184.3ºC • Mercury: 356.9ºC • Olive oil: 300ºC • Jet fuel: 163ºC

18. Identify the phase change represented in the photograph.

19. Substance loses heat energy GAS LIQUID

20. Condensation • G  L • Gas RELEASES heat energy GAS Gas loses heat energy LIQUID

23. Identify the phase change represented in the photograph.

24. Substance ABSORBSenergy GAS SOLID

25. Sublimation • Solid  Gas • Solid ABSORBS energy GAS Solid absorbs heat energy Solid

26. Mt. Everest loses some snow cover due to common windstorms. Snow is also constantly lost, invisibly, due to sublimation

27. Moth balls are used when storing clothing and other articles susceptible to damage from mold or moth larvae. Moth balls commonly undergo the process of sublimation. Sublimation is the process in which a solid changes directly to its gaseous phase, skipping the liquid phase.

28. Humid air to condenses into frost patterns, for example in single-layer window glasses and windshields.

29. Deposition Substance LOSES energy SOLID GAS

30. Deposition • G  S • Gas RELEASES energy https://www.youtube.com/watch?v=Ft2KgtlP8Lk Solid Solid releases heat energy GAS

32. Let’s summarize… • List the different types of phase changes. 2. Explain what happens to heat energy in each phase change.

33. 5 2 1 4 3 A B C

34. When a liquid becomes a solid, energy • does not change • is released • is absorbed • is first absorbed, then released

35. _______ is the process in which liquid changes to gas below the boiling point.   Sublimation Condensation Evaporation Combustion

36. On a hot day, the outside of a glass containing a cold drink becomes frosty. When touching the glass, it feels • water that has passed through the glass • water that has condensed from a gas in the air • water that has solidified • water that has absorbed energy

37. The change of a liquid to a solid is called freezing melting sublimation vaporization

38. When substances go directly from the solid phase to the gas phase, the phase change is called sublimation condensation evaporation vaporization

39. Mass number: 137 • Atomic #: 56 • # of neutrons: 137-56 81 neutrons

40. http://www.youtube.com/watch?v=XaDxwe8l3us&feature=related