1 Avogadro Number
The Avogadro constant is named after the Italian scientist Amedeo Avogadro (1776–1856), who, in 1811, first proposed that the volume of a gas (at a given pressure and temperature) is proportional to the number of atoms or molecules regardless of the nature of the gas. Avogadro’s number, number of units in one mole of any substance (defined as its molecular weight in grams), equal to 6.02214076 × 10 23. 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 also Avogadro’s law. 1: Italian scientist Amadeo Avogadro, whose work led to the concept of the mole as a counting unit in chemistry. The number 6.02 × 10 23 is called Avogadro's number, the number of representative particles in a mole. It is an experimentally determined number.
1 Avogadro Number
| Value of NA[1] in various units |
|---|
| 6.02214179(30)×1023 mol−1 |
| 2.73159757(14)×1026 lb-mol−1 |
| 1.707248479(85)×1025 oz-mol−1 |
The Avogadro constant (symbols: L, NA) is the number of particles (usually atoms or molecules) in one mole of a given substance.[2] Its value is equal to 6.02214129(27)×1023 mol−1.[3] The constant was named after the ItalianscientistAmedeo Avogadro.
The measurement of Avogadro's constant was refined in 2011 to 6.02214078×1023 ± 0.00000018×1023.[4]
An old term closely related to the Avogadro constant is Avogadro's number. Avogadro's number is the number of atoms in 12 grams of the carbonisotopecarbon-12. Avogadro's number is a dimensionless quantity and has the numerical value of the Avogadro constant given in base units.
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1 Avogadro Numbers
- ↑Mohr, Peter J. (2008). 'CODATA Recommended Values of the Fundamental Physical Constants: 2006'(PDF). Rev. Mod. Phys.80: 633–730. Bibcode:2008RvMP...80..633M. doi:10.1103/RevModPhys.80.633.Unknown parameter
|coauthors=ignored (|author=suggested) (help)Direct link to value. - ↑Johnston, Lesley (2008). Salters Advanced Chemistry: Revise Chemistry For Salters AS (Second ed.). Heinemann. p. 2. ISBN978-0-435-63154-3.
- ↑'Avogadro constant'. National Institute of Standards and Technology. Retrieved 2013-11-07.CS1 maint: discouraged parameter (link)
- ↑Andreas, Birk; et al. (2011). 'Determination of the Avogadro Constant by counting the atoms in a 28Si Crystal'. Physical Review Letters. 106 (3). arXiv:1010.2317. Bibcode:2011PhRvL.106c0801A. doi:10.1103/PhysRevLett.106.030801.
What Is Avogadro Number
1 Mole Number Avogadro