Phases of Matter
Notes #11
To the Computers!
• Get your computer and go to the following site:
https://phet.colorado.edu/en/simulation/legacy/states-of-matterbasics
• Or you can search for “PhET States of Matter basics”
• This is one of the simulations you need to download to run
Molecular Motion (not notes)
• What do the circles represent?
• What are the circles doing?
• What happens when they are heated up?
Molecular Motion (notes)
Atoms and molecules are always in motion.
• This includes moving around and
vibrating
• We feel this motion as heat: the faster
the movement, the higher the
temperature
• “Absolute zero” is the temperature at
which all motion stops
Atoms moving around
Atoms vibrating
0º C: atoms
are moving
slowly
100º C: atoms
are faster
?
Absolute Zero (not notes)
• Absolute zero is -273.15 ºC or -459 ºF
• This is 0 on the Kelvin scale of
temperature, another system commonly
used in science
• As far as we can tell, absolute zero is a
“theoretical” temperature: it isn’t
actually possible to reach it
Solids (not notes)
• What do you notice about the atoms/molecules in a solid?
Solids (notes)
• Stable shape and volume
• Atoms/molecules are strongly
attracted and close together
Atoms/molecules in solids
line up in rigid structures.
Liquids (not notes)
• How are the atoms/molecules behaving now?
• How are they different from a solid?
Liquids (notes)
• Stable volume but not stable shape
• Atoms/molecules are weakly
attracted and further apart
Atoms/molecules in liquids are
free to move past each other.
Gases (not notes)
• How are the atoms/molecules behaving now?
• How are they different from a solid and liquid?
Gases (notes)
• No stable shape or volume
• Atoms/molecules have no
attraction and are very far apart
Atoms/molecules in gases
are far apart and moving
independent of each other.
Plasma (not notes)
• Plasma is sometimes listed as a 4th state of matter
• Plasma is above gases in energy, where the electrons begin to come
off the atoms
• The sun is an example of plasma, but it can be produced in a variety
of situations such as lightning strikes
Phase Change (not notes)
• A phase change is when a substance goes from one phase (solid,
liquid, or gas) to another
Phases of Matter Diagram (notes)
Gas
Boiling/
Evaporation
Sublimation*
Condensation
Liquid
Melting
Increasing Heat
*Students are not responsible for knowing these
Solid
Freezing
Deposition*