Dalton (unit)
The dalton or unified atomic mass unit (symbol: Da, amu or u) is a unit of measurement for measuring the mass of atoms, equalling ¹⁄₁₂ of the mass of the carbon-12 isotope, the most abundant form of carbon atoms in nature.[1]
History
The unit is named after English chemist and physicist John Dalton (1766 – 1844). 1 atomic mass unit is approximately 1.66 × 10-27 kg, or 1.66 × 10-24 g.[2]
Atomic physics
In atomic physics, 1 amu can be expressed as roughly 931 MeV (M = 106, 1 eV ≈ 1.60 × 10-19 J) due to mass-energy equivalence, illustrated by ΔE = Δmc2.[3][4]
Dalton (unit) Media
French physicist and Nobel laureate (1870-1942) Jean Perrin.
Portrait plaque of Johann Josef Loschmidt on the wall of a building in Vienna (Lacknergasse 79). *Taken 2018-02-27 16:41:13 at GPS coordinates 48.227339, 16.333528 (per EXIF).*Plaque at Google coordinates 48.227285, 16.333515 per Google Street View. This file is a copy of
- Wien18 Lacknergasse079 2018-
Ball-and-stick model of the unit cell of silicon. X-ray diffraction measures the cell parameter, a, which is used to calculate a value for the Avogadro constant.
Related pages
References
- ↑
- Mills, Ian. Quantities, Units and Symbols in Physical Chemistry International Union of Pure and Applied Chemistry; Physical Chemistry Division (1993)International Union of Pure and Applied Chemistry and published for them by Blackwell Science Ltd. ISBN 0-632-03583-8.
- Consultative Committee for Units (CCU); Report of the 15th meeting (17 –18 April 2003) to the International Committee for Weights and Measures. Retrieved 14 Aug 2010.
- IU14. IUPAC Interdivisional Committee on Nomenclature and Symbols (ICTNS). Retrieved 2010-08-14.
- ↑ Atomic mass unit | Definition, Description, Uses, & Facts. Britannica (November 11, 2024). Retrieved November 30, 2024.
- ↑ Converted number: Conversion from eV to J. National Institute of Standards and Technology (NIST) (2022). Retrieved November 30, 2024.
- ↑ Nuclear Binding Energy and the Mass Defect. Boston University. Retrieved November 30, 2024.