Phases of Matter Notes
Gases, liquids, and solids are all made up of microscopic particles, but the behaviors of these particles differ in
the three phases.
Note that:
 Particles in a:
o gas are well separated with no regular arrangement.
o liquid are close together with no regular arrangement.
o solid are tightly packed, usually in a regular pattern.

Particles in a:
o gas move freely at high speeds.
o liquid move about and slide past each other.
o solid vibrate (jiggle) but generally do not move from place to place.
STATES OF
MATTER
SOLID
LIQUID
GAS
Arrangement
of particles
The particles are very
closely packed.
The particles are closely packed
but there are more empty
spaces between them compared
to the solid state.
The particles are very far
apart from each other.
Forces of
attraction
between
particles
The very strong forces of
attraction restrict the
movement of the particles.
The particles in a solid are
held in fixed positions.
The forces of attraction are
weaker than in the solid state.
The particles are no longer held
in fixed positions.
The forces of attraction
are very weak. The
particles move randomly
in all directions at great
speed.
Volume and
shape
Solids have fixed volumes
and shapes.
Liquids have fixed volumes.
However, they do not have fixed
shapes but take the shapes of
the containers.
Gases do not have fixed
shapes or volumes.
Types of
movement
Particles move only by
vibration.
Particles vibrate and slide past
one another.
Particles vibrate and
move freely all over.
Kinetic
(movement)
energy of
particles
The kinetic energy of the
particles is low.
The kinetic energy of the
particles is high, on average.
The kinetic energy of the
particles is very high and
they move at high speed.
Compressibility
Very difficult to be
compressed because the
particles are packed closely.
Not easily compressed because
the particles are packed closely.
Easily compressed
because the particles are
far apart.
Rate of
diffusion
Very low
Average
Very high
Plasma is the fourth phase of matter. Plasma is a super heated gas containing positively and negatively
charged particles called ions. It shares the same characteristics as gases. Plasma is very rare on Earth but
makes up 99% of the universe! Plasma can be found in lightning, stars, suns, auroras, and plasma balls.
Phase Changes of Matter
All matter is made of particles which are constantly moving, colliding with each other and the walls of a
container. As energy is added to or removed from matter, it can change form one phase to another. When
something such as water turns from being water to being ice, it is called a phase change. There are different
changes that can take place.
Melting is the change of a solid to a liquid.
Melting occurs when a substance absorbs
heat energy.
Solid – Liquid
Phase Changes
Freezing is the change of a liquid to a solid.
Freezing occurs when a substance loses
heat energy.
Liquid – Gas
Phase Changes
Vaporization is the
change of a
substance from a
liquid to a gas.
There are two types
of vaporization.
Evaporation occurs
when a substance
absorbs enough heat
energy so that only
the surface of the
liquid is vaporized.
Boiling occurs when
enough heat energy
is supplied so that
particles travel to the
surface of the liquid
and then into the air.
Condensation is the change of a substance
from a gas to a liquid. It takes place when
water vapor in the air condenses from a gas,
back into a liquid form.
Solid – Gas
Phase Changes
Sublimation is the change of a substance
from a solid to a gas. In some solids, the
surface particles sublime and escape
directly into the gas phase. They do not
pass through the liquid phase.
Energy determines the state!
Add or Subtract (Heat) Energy. . .


When energy is added, particles move faster! (Heated)
When energy is taken away, particles move slower! (Cooled)