Download Separation Techniques Separation Techniques

Brainteaser 8/21/12
Homogenous or heterogeneous??
If you have to use a microscope in order to
see the different substances in a mixture,
that mixture is _____________.
Apple juice, salt water, and soda are all
examples of a _____________ mixture.
These types of mixtures are also known as
_____________.
Separation
Techniques
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Separating Mixtures
✦
Most matter exists naturally as mixtures.
✦
Because the substances in a mixture are
physically combined, the processes used to
separate a mixture are physical processes
that are based on the difference in physical
properties of the substances.
✦
Sometimes it is very easy to separate a
mixture; separating a mixture of pennies
and nickels is not a difficult task.
Separating Mixtures
✦
Heterogeneous mixtures composed of
solids and liquids are easily separated by
filtration.
✦
Filtration is a technique that uses a porous
barrier to separate a solid from a liquid.
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Separating Mixtures
✦
Most homogeneous mixtures can be
separated by distillation
✦
Distillation is a separation technique that
is based on differences in the boiling points
of the substances involved.
Separating Mixtures
✦
When precisely controlled, distillation can
separate substances having boiling points
that differ by only a few degrees.
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Separating Mixtures
✦
Crystallization is a separation technique
that results in the formation of pure solid
particles of a substance from a solution
containing the dissolved substance.
Separating Mixtures
✦
Chromatography is a technique that
separates the components of a mixture
(called the mobile phase) on the basis of
the tendency of each to travel or be drawn
across the surface of another material
(called the stationary phase).
✦
The separation occurs because the various
components of the ink spread through the
paper ant different rates.
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Separating Mixtures
Separating Compounds
✦
Only separation technique
that is used for compounds
✦
This is a CHEMICAL
separation techniques
✦
Electrolysis is the passage
of a direct electric current
through an ion-containing
solution
✦
In the picture, water is being
separated into hydrogen
and oxygen gas
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