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 Liquid Gas Solid Liquid Solid Gas No definite shape or volume.
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.
Gas
Liquid
Gas
Solid
Liquid
Solid
Gas

4. Observe the phase change diagram
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: ºC

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

10. Substance loses heat energy
LIQUID
SOLID

11. Freezing
L  S
Liquid RELEASES heat energy
Substance loses heat energy

12. Identify the process occurring in the animation.

14. Substance ABSORBSenergy
LIQUID
GAS

15. Vaporization GAS LIQUID 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 GAS LIQUID G  L Gas RELEASES heat energy
Gas loses heat energy
LIQUID

23. Identify the phase change represented in the photograph.

24. Substance ABSORBSenergy
SOLID
GAS

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

26. Mt. Everest loses some snow cover due to common windstorms
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. Substance LOSES energy
Deposition
Substance LOSES energy
SOLID
GAS

30. Deposition G  S Gas RELEASES energy Solid GAS
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 1 2 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. water that has passed through the glass
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