Chemistry / Unit 1 Chem 0037 short lesson, about 20 seconds
Pure Substance
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The idea
A pure substance has a constant composition, so every sample of it has exactly the same makeup and physical properties.
In practice
Any sample of pure copper has the identical density and melting point regardless of the mine it came from.
Where people slip
"Pure" here means constant composition, not "natural" — a substance made in a lab can be equally pure as one from a plant.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
Builds on
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