Page 170 - DK Children's Encyclopedia

Mixtures SEE ALSO

▸ ▸ Changing states
p.57

A mixture is made when we mix different materials ▸ ▸ Gases p.117
together and they can be easily separated back out into ▸ ▸ Liquids p.148
their original parts. Mixtures can be made from solids, ▸ ▸ Rocks and

liquids, and gases. There are three main ways of minerals p.214
separating mixtures. ▸ ▸ Solids p.234

Sifting Filtering
We can use a sifter to separate large solids Filters are made from materials
from small ones, or solids from liquids. A with tiny holes in them. The
sifter is made from crisscrossed wire with holes catch solids that are
small holes that let some solids through. too big to fit through, but
The shells are let liquids pass.
large solids
that are caught
by the sifter.

A mixture of sand
and water is poured
Grains of sand into the filter.
are tiny solids
that fall through
the sifter.

The filter catches
the sand but not
the water.

The liquid
changes to gas
and the solid will
be left behind.
The water that lands
in the beaker has no
Evaporation sand in it.
Some solids such
as salt dissolve
(disappear) when they
are mixed into a liquid.
If we heat the liquid, Compounds
we can take out the Some materials that are
joined together can’t be
solid in a process easily separated by sifting,
called evaporation. filtering, or evaporation.
These materials are not
mixtures, they are
compounds. Iron and
Heat causes the sulfur make the
liquid to boil and compound iron sulfide.
change to gas.
Iron sulfide

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