Avogadro's number

American  

noun

Chemistry.

1. the constant, 6.022 × 10 23 , representing the number of atoms, molecules, or ions in one mole of a substance. N

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Avogadro's number Scientific  

1. The number of atoms or molecules in a mole of a substance, approximately 6.0225 × 10 ²³. It is based on the number of carbon atoms in 12 grams of carbon 12.

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Etymology

Origin of Avogadro's number

First recorded in 1925–30; see origin at Avogadro's law

Example Sentences

The things I do manage to remember bear an inverse relationship to any usefulness: Avogadro’s number, the Fibonacci sequence, the smell of Chanel No. 5.

From New York Times • May 30, 2019

Physics prof: Do you know what Avogadro’s number times Planck’s constant equals?

From Washington Post • Apr. 21, 2016

It was Avogadro who developed the idea of a fixed number of atoms and molecules in a mole, and this special number is called Avogadro’s number in his honor.

From Textbooks • Aug. 12, 2015

Like Avogadro's number or the rules of subjunctive verbs, the War of 1812 is one of those things that you learned about in school and promptly forgot without major consequence.

From Slate • May 25, 2012

The principle led to the much later adoption of Avogadro’s number, a basic unit of measure in chemistry, which was named for Avogadro long after his death.

From "A Short History of Nearly Everything" by Bill Bryson