Chemistry / Unit 1 Chem 0038 short lesson, about 20 seconds
Element
Captions available
The idea
An element is a pure substance that cannot be broken down into simpler substances by ordinary chemical changes.
In practice
Heating pure iron, however strongly, never separates it into two or more different substances.
Where people slip
A sample looking uniform does not make it an element — check whether it resists chemical breakdown, not only its appearance.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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