Magnetic separation uses magnets to separate mixtures where one substance is attracted to magnets and the other is not, such as separating iron filings from sand. Decantation involves pouring off the liquid layer from a mixture like water and sand so that the denser sediment remains behind. Filtration uses a filter to catch solid particles in a mixture while allowing the liquid to pass through, such as filtering coffee grounds from water.

1. SEPARATING MIXTURES
By Andrés Arévalo

2. 1. MAGNETIC SEPARATION
We can use magnetic
separation if we want to
separate substances that
are attracted by magnets
and substances that are not
(attracted by magnets).

3. For example, if we have
a mixture of sand and
iron filings, the magnet
will attract the iron
filings but will not do
that with the sand.

4. 2. DECANTATION
For example, in a mixture of
water and sand.
When we decant a liquid,
we pour off the liquid so that
the sediment (the sand)
remains in the container.

5. We can also decant a
mixture of oil and water.
The oil stays at the top
because the water has
more density than the oil.

6. 3. FILTRATION
In filtration, a filter is
used to catch the
particles but allows
the liquid to pass.
Paper filter and coffee grounds.

7. 4. EVAPORATION
In evaporation, we
separate a mixture of a
liquid and a solid.
When we heat this
mixture, the water
evaporates and the
sediments remain.

8. Evaporation is used to separate
salt and water in these salt ponds.

9. 5. DISTILLATION
Liquids evaporate when they boil. This is what we call
boiling point (punto de ebullición). However, some liquids
boil earlier than others.
Alcohol evaporates earlier than water.

10. If we want to
separate a
mixture of water
and alcohol:
1. We heat the mixture.
2. Alcohol evaporates
earlier because it has
a lower boiling point.
3. Alcohol cools down
and condensates. So
it becomes liquid
again.
4.The liquid
alcohol is
collected.