Chemistry / Unit 3 Chem 0370 short lesson, about 20 seconds
Avogadro's Number
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The idea
Avogadro's number is the count of entities in one mole, fixed by 2019 SI redefinition at 6.02214076×10^23 per mole.
In practice
A mole of carbon atoms and a mole of water molecules hold this same fixed count, though their masses differ.
Where people slip
Older sources call this figure "experimentally determined"; the 2019 redefinition made it an exact constant, not a measured one.
Your place on the trail
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Builds on
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