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Avogadro’s number
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How to use the ideal gas law
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Avogadro’s number

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Also known as: Avogadro constant
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Key People:
Amedeo Avogadro
Joseph Loschmidt
How to use the ideal gas law
How to use the ideal gas lawOverview of how Avogadro's number is used to measure the number of units of any substance.
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Avogadro’s number, number of units in one mole of any substance (defined as its molecular weight in grams), equal to 6.02214076 × 1023. The units may be electrons, atoms, ions, or molecules, depending on the nature of the substance and the character of the reaction (if any).See alsoAvogadro’s law.

The Editors of Encyclopaedia BritannicaThis article was most recently revised and updated by Erik Gregersen.