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; 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

The relationships between formula mass, the mole, and Avogadro’s number can be applied to compute various quantities that describe the composition of substances and compounds, as demonstrated in the next several example problems.

From Textbooks • Feb. 14, 2019

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

From Washington Post • Apr. 21, 2016

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