Using Physical Properties and
Physical Changes to
Separate Mixtures
Trail Mix
is a type of mixture.
A Mixture
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A mixture is a combination of different
substances that are in the same container or
place.
Can you name other examples of mixtures?
Candy Mixture
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How might you
separate a bag of
Halloween candy?
What physical
properties would you
use?
Color? Brand Name?
Type? Wrapper
Color? Size? What
you want to eat first?
Some mixtures are easy to
separate.
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Mixtures can be easily separated when:
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You can easily see the different parts.
You can easily pick out the different parts.
In this bowl you can easily see the
different colors and you can easily
pick out the pieces.
You can separate the pieces based
on the physical property of color.
Some mixtures may take several
steps to separate.
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Mixtures take more steps to separate
when:
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You cannot easily see all the parts.
Some of the parts are too small to pick up by
hand.
In this pile you can see there are rocks of
different sizes. There is also dirt in the
mixture.
This mixture cannot be easily separated by
hand.
1. Separating a rock mixture.
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How could you
separate this mixture
to make one pile of
rocks and one pile of
dirt?
What physical
property can you use
to separate the
mixture?
The physical property we can use to separate
the rock mixture is size. To help us do this we
can use a filter.
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The filter will keep the large rocks on top
and let the small dirt pass through.
Rocks will stay
on top of the
filter screen.
Small dirt will fall
through the screen to
the bottom.
2. Separating a sugar mixture.
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In this mixture sugar was dissolved into a
glass of water.
What physical property and physical
change can you use to separate the mixture
so you have the sugar left?
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The physical property we can use to separate the
sugar mixture is solubility.
We will also use the physical change of vaporization.
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The sugar is soluble, which means it
dissolved in the water.
We can put the cup in the sun to help
the water vaporize (evaporate).
When energy is added to the
water, the water will turn into
a gas and leave the cup.
The sugar will be left behind
and separated from the water.
3. Separating wood chips and
rocks.
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In this mixture wood chips and
rocks are mixed together.
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What physical properties can
you use to separate the
mixture so you have one pile
of rocks and one pile of wood
chips?
The first physical property we can use to separate
the wood chips and rocks is density.
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We can add the wood chips and
rocks to a container of water.
The wood chips will float.
We can scoop the wood chips out of
the water.
This will give us the pile of wood
chips.
We then use the physical property of size to
separate the water from the rocks.
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We then use a filter to filter the
water out of the rocks.
This way are are left with the pile
of rocks.
4. Separating iron
filings and sand.
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In this mixture iron filings
and sand are mixed
together.
What physical property
can you use to separate
the mixture so you have
one pile of iron filings
and one pile of sand?
Iron filings are small pieces of iron.
These are used in Etch A Sketches.
We use the physical property of magnetism to
separate the iron filings from the sand.
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The iron filings are magnetic and can be
picked up by a magnet.
The sand is not magnetic and will be left
behind.
5. Separating sand and sugar.
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In this mixture sand and
sugar are mixed together.
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What physical property
and physical change can
you use to separate the
mixture so you have one
pile of sand and one pile
of sugar?
Separating this mixture will take several steps.
We first use the physical property of solubility.
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Sugar is soluble (will dissolve) in water.
Sand is not soluble (will not dissolve) in water.
We mix the sand and sugar with water.
The sugar will dissolve in the water.
The sand will stay separated in the water.
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Next use the physical property of size. We will need
a coffee filter or other filter paper.
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The water and dissolved sugar
will go through the filter paper.
The sand is too large and will
stay on top of the filter paper.
We collect the sand from the
top of the filter paper. This will
give us a pile of sand.
After the sand is separated, we then need to
separate the sugar from the water. We will use the
physical change of vaporization.
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We can allow the water in to vaporize
(evaporate).
The sugar will be left behind. This will give
us a pile of sugar.
Now you can practice.
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Turn your paper over.
You will now complete “The Recycling
Factory” assignment.