DIFFUSION

Food, water, and
other substances
are made of
different kinds of
particles, such as
molecules and
ions.

Particles are
always moving,
like dancers on a
crowded dance
floor.

You can tell how
particles will tend to
move if you know
how crowded they
are.

Concentration refers
to how crowded
particles are.
A juice concentrate is a
very strong form of
juice. It has many more
juice particles than
regular juice does.
When
you mix the
 In a concentrate, the
concentrate
with
juice particles are very
water, the juice
crowded.
particles spread out in
the water.
•They tend to move
away from places where
they are concentrated
Thus,
the particles
become less
concentrated.
Particles will
continue to move
from areas of high
concentration to
areas of low
concentration until
they reach
equilibrium.
•This process is called diffusion.

Watch the demonstration with food coloring
in water, then answer the following:
Explain
why the ink spreads out in the water.
Use the words concentration and diffusion in your
answer.
The dye is very concentrated when it enters the
water. The dye diffuses through the water to
lower concentrated areas until equilibrium is
reached.
 Temperature
 Density
of the Diffusing
Substance
 Medium of Diffusion
 Concentration Gradient
Factors affecting
diffusion