PHASE CHANGES
KINETIC THEORY OF MATTER
Matter is made up of particles
which are in continual
random motion.
WHAT ARE THE 4 STATES OF
MATTER?
Solid
Plasma
Liquid
Gas
SOLIDS:
• Solids have a definite shape
and volume
• usually organized, crystalline
solid
• Softer solids will have no
pattern, amorphous solid.
• packed tightly together
• Vibrate in place
• Liquids have a definite
volume
• Liquids take the shape of
their container.
• Liquids are a fluid
• Far enough apart to slide
over one another
• Energy level is greater than
in solids
PARTICLES IN LIQUIDS:
• No definite volume or
shape.
• Gasses spread out to fill the
entire space given.
• Can be squeezed together
• Particles are very far apart
and move freely
• Collide frequently
• Have LOTS of energy
PARTICLES IN GASES:
PARTICLES IN PLASMA:
• Plasma is a lot like a gas,
but the particles are
electrically charged.
• Have indefinite shape
and volume.
• EXTREMELY energetic
• Lightning is a plasma.
• Used in fluorescent light
bulbs and Neon lights.
STATES OF MATTER
SOLID
Tightly packed,
in a regular
pattern
Vibrate, but do
not move from
place to place
LIQUID
Close together
with no regular
arrangement.
Vibrate, move
about, and slide
past each other
GAS
Well separated
with no regular
arrangement.
Vibrate and
move freely at
high speeds
PLASMA
Has no definite
volume or shape
and is composed of
electrical charged
particles
WHAT IS A PHASE CHANGE?
• A change from one state of
matter to another
• Phase changes are physical
changes because they do not
affect the chemical make up
of a substance.
WHAT HAPPENS DURING
A PHASE CHANGE?
• During a phase change
heat energy is either
absorbed or released
• Heat energy is released as
molecules slow down and
move closer togetherexothermic
• Heat energy is absorbed as
molecules speed up and
expand-endothermic
MELTING
• Phase change from a
solid to a liquid
• Molecules speed up,
move farther apart, and
absorb heat energy
FREEZING
• Phase Change from a
liquid to a solid
• Molecule slow down,
move closer together
and release heat
energy.
VAPORIZATION (BOILING)
• Phase change from a
liquid to gas. It occurs at
the boiling point of
matter.
• Molecules speed up,
move farther apart, and
absorb heat energy.
EVAPORATION
• Phase change from a
liquid to a gas on the
surface of a liquid (type
of vaporization).
• Molecules speed up,
move farther apart, and
absorb heat energy.
CONDENSATION
• Phase change from a
gas to a liquid.
• Molecule slow down,
move closer together
and release heat
energy.
SUBLIMATION
• Phase change from a
solid to a gas.
• Molecules speed up,
move farther apart, and
absorb heat energy.
DEPOSITION
• Phase change from a
gas to a solid.
• Molecules slow down,
move closer together
and release heat
energy.
PHASE CHANGE OF WATER
1. Why is there no
change in
temperature during
a phase change?
2. Define melting and
boiling point.
3. What is the melting
and boiling point of
water?
4. At what
temperature does
water freeze and
become a solid?