Solutions, colloids, and suspensions are three types of mixtures. Solutions are homogeneous mixtures with particles smaller than 1 nm that remain mixed and do not separate. Colloids have slightly larger particles from 1-100 nm that appear cloudy but also remain mixed. Suspensions have the largest particles over 100 nm that can separate upon standing and can be separated by filtration.

1. Types of Mixtures

2. Solutions
• Solutions are homogeneous mixtures made up of
two components.
• The part of the solution that does the dissolving
is called the solvent.
• The part of the solution that gets dissolved is
called the solute.
• In a sugar water solution, what is the solute?
• Sugar
• In a sugar water solution, what is the solvent?
• Water

3. Solutions (continued)
• The solute particles are < 1 nm in diameter.
• How large are these particles in cm?
• 0.0000001 cm
• As a result, solutions often appear clear.
• Due to the extremely small particle size solutions
remain mixed and do not separate (settle out) upon
standing.
• Solutions cannot be separated by filtration (particles
are so small they pass through the paper with the
solvent.
• Examples include: kool-aid, flat soft drink

4. Solutions

5. Colloids
• Colloids are heterogeneous mixtures.
• The particles mixed into the main component are
between 1 and 100 nm in diameter.
• Due to the slightly larger particle size, colloids
appear cloudy.
• Although the particles are larger than in a
solution, they are still small enough that they stay
mixed and do not separate upon standing and
cannot be separated by filtration.
• Examples: milk, whipped cream

6. Colloids

7. Tyndall Effect
• Particles in a colloid are large enough that
they will reflect (scatter) light.
• This phenomenon is referred to as the Tyndall
Effect.

8. Tyndall Effect

9. Suspensions
• Suspensions are also heterogeneous mixtures.
• The particles in a suspension are the largest
and have a diameter > 100 nm.
• Due to the larger size these particles will
separate (settle out) upon standing.
• If all of the particles have separated, the liquid
may appear clear. If not, the liquid may
appear cloudy.

10. Suspensions
• The larger particle size allows for suspensions
to be separated by filtration.
• The Tyndall effect may be observed if the
particles have not settled out.
• Examples: muddy water, Italian salad dressing.

11. Suspension

12. Solution, Colloid,
or Suspension
•Recently opened
soft drink
•Fog
•Food coloring in
water
•Blood
•Milk
•Pure air
•Sugar water
•Paint