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Elements, Compounds and Mixtures
Compounds.
A compound is a substance made from two or more elements
which have reacted chemically with
each other.
A compound is a completely new
material
which will often have totally different properties
from the elements which made
it.
For example
The element sodium is a highly
reactive metal.
The element chlorine is a yellow-green
poisonous gas (non-metal).
When the two react together, they form a compound called sodium chloride.
Sodium chloride is common
salt, which you eat with food.
You wouldn't want to eat the elements!
You cannot separate the elements of a compound by physical methods.
It can only be done by using more
chemical reactions
or by passing electricity through it (if it conducts electricity).
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