Avogadro's number

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Related to Avogadro constant: atomic mass unit, gas constant, Pv=nrt

Avogadro's number

(ävōgä`drō) [for Amedeo AvogadroAvogadro, Amedeo, conte di Quaregna
, 1776–1856, Italian physicist, b. Turin. He became professor of physics at the Univ. of Turin in 1820. In 1811 he advanced the hypothesis, since known as Avogadro's law, that equal volumes of gases under identical conditions of pressure
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], number of particles contained in one molemole,
in chemistry, a quantity of particles of any type equal to Avogadro's number, or 6.02×1023 particles. One gram-molecular weight of any molecular substance contains exactly one mole of molecules.
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 of any substance; it is equal to 602,252,000,000,000,000,000,000, or in scientific notation, 6.02252×1023. For example, 12.011 grams of carbon (one mole of carbon) contains 6.02252×1023 carbon atoms, and 180.16 grams of glucose, C6H12O6, contains 6.02252×1023 molecules of glucose. Avogadro's number is determined by calculating the spacing of the atoms in a crystalline solid through X-ray methods and combining this data with the measured volume of one mole of the solid to obtain the number of molecules per molar volume.

Avogadro's number

[¦a·və¦gäd·drōz ‚nəm·bər]
(physics)
The number (6.02 × 1023) of molecules in a gram-molecular weight of a substance.
References in periodicals archive ?
But the problem now is that not everyone agrees on the true number for the Avogadro constant.
As long as the Avogadro constant stays constant, it will be useful for defining the kilogram.
Equivalent procedures were used in the x-ray spacing measurements for silicon crystals for the XRCD method deriving the Avogadro constant (17).