Physical

1
Physical Chemical Changes
2
Physical vs. Chemical Change
Physical Change -
Change that affects only the physical properties
of a substance

• Physical properties include
• Size, Shape and Phase of matter

Appearance changes not chemical makeup
3
Physical vs. Chemical Change
Chemical Change -
Results from chemical reactions in which one or
more new substances are formed
End products are chemically different from the
original.
Corrosion-dissolving away metal-rusting.
4
Physical vs. Chemical Change
Identify the following as physical or chemical
change.
Ice cube melting.
People eating.
Wood burning.
Slicing an apple into pieces.
5
Changes in Matter - Continued

• Melting Point
• Temperature at which a solid changes
• to a liquid
• Example Ice ? water

• Freezing Point
• Temperature at which a liquid changes
• to a solid
• Example Water ? Ice (0C)

6
Changes in Matter

• Boiling Point
• Temperature at which a liquid changes
• into a gas
• Example Water ? vapor (100 C)

7
Changes in Matter - Continued

• Evaporation-
• process at which a liquid changes to a gas at
  boiling point
• Example water boils to form steam

8
Changes in Matter - Continued

• Condensation
• Process at which a gas becomes a liquid
• Gas cooled below its boiling point
• Example water vapor ? water, dew in the
  morning, glass of ice tea in hot weather.

9
Changes in Matter - Continued

• Sublimation
• When a solid changes directly to a gas
• The matter doesnt melt
• Examplesnow, dry ice and glaciers

• Deposition-
• Gas changes directly into a solid

10
Changes in Matter - Continued

• Exotic Super Hot
• Nucleus of atom comes apart
• Particle accelerates
• Exotic Super Cold
• Below -270 C
• Superfluids from gases