Phases, Phase Changes, Chemical and Physical Changes
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Transcript of Phases, Phase Changes, Chemical and Physical Changes
Phases, Phase Changes,
Chemical and Physical Changes
By:Brianna ShieldsMarch 19, 2007
DO NOW• 1. What tool is used to measure mass?
• 2. What is one unit used to label density?
• 3. What is volume?
GOAL• To discuss the states of matter and the
terms relative to changes in state• To distinguish between chemical and
physical changes
QuickTime™ and aSorenson Video 3 decompressorare needed to see this picture.
Phases of Matter• Solid • 1. Has a definite shape
• 2. Has a definite volume
Phases of Matter• Solid • 3. Particles are tightly
packed (can’t move or flow well)
• 4. Low energy
Phases of Matter• Solid • 5. May be crystals with
repeating patterns– Ex: salt
Phases of Matter• Solid • 6. Amorphous solids
lose shape/flow like slow moving liquids– Ex: candle wax, window
glass, tar
Phases of Matter• Liquid • 1. No definite shape-
takes the shape of the container
• 2. Has a definite volume
Phases of Matter• Solid • 3. Particles are packed
loosely and flow slowly• 4. Average energy
Phases of Matter• Liquid • 5. Varying viscosities=
resistance of a liquid to flow– Honey has a high viscosity
Phases of Matter• Gas • 1. No definite shape-
takes shape of container• 2. No definite volume
Phases of Matter• Gas • 3. Particles are spread
far apart- fill all spaces• 4. Contantly moving and
bumping into eachother• 5. High energy
Phases of Matter• Gas • 6. Particles can be
squeezed in closer– Bumping into eachother and
walls causes pressure
Phase Website• Phases of matter at the molecular level
Phase Summary Chart• Work with a partner to fill in the phase
summary chart
Phase Changes• Phase
Changes• Matter such as water can
change from phase to phase by adding or taking away heat energy
Phase Changes• Melting • Solid to liquid
• Must take in heat energy• M.P of water = 0 C or 32 F
Examples of Melting
Phase Changes• Freezing • Liquid to solid
• Must lose heat energy• F.P of water = 0 C or 32 F
Examples of Freezing
Phase Changes• Evaporati
on• Liquid to gas• Must gain heat energy• B.P of water = 100 C or
212 F
Examples of Evaporation
Phase Changes• Condensatio
n• Gas to liquid• Must lose heat energy
Examples of Condensation
Phase Changes• Sublimati
on• Solid skips to gas• Must gain a lot of heat
energy• Ex:
– Freezer Frost– Dry Ice– Cirrus Clouds
Phase Change Website• Click here to view a phase change
Phase Change Diagram
Assessment• Determine what phase change is the
opposite of evaporation. Explain
Assessment• What type of phase change is seen in
this picture? Explain what occurs during this phase change
Assessment• What type of phase change is seen in
this picture? Explain what occurs during this phase change
Assessment• What phase change is the opposite of
freezing? Explain
Physical and Chemical Changes• Physical
Change• Change in the
appearance of a substance without changing its identity
• The atoms remain unchanged
Physical and Chemical Changes• Chemical
Change• A substance changes into
a new and different substance
• The atoms are altered• Often involves chemical
rx
Assessment: Physical or Chemical Change????