Electronvolt
The electronvolt (symbol: eV) is a non-SI unit of energy that has been accepted for use with the SI by the CIPM.[1] It is defined as the kinetic energy gained by an electron on passing through a potential difference of one volt in vacuum:[1] as such, its value in SI units is determined by the measured value of the elementary charge. The 2006 CODATA recommended value is 1 eV = 1.602 176 487(40) × 10−19 J.[2]
In chemistry, it is often useful to express the electronvolt as a molar quantity, whose value in SI units is determined by the measured value of the Faraday constant. The 2006 CODATA recommended value is 1 eV = 96.485 3399(24) kJ mol−1.
In particle physics, multiples of the electronvolt are also used as a units of mass based on the principle of mass–energy equivalence. The dimensionally correct unit of mass for use with the SI would be eV/c2, although the division by the square of the speed of light is often assumed and masses quoted simply in megaelectronvolts (MeV).
References
- ↑ 1.0 1.1 The International System of Units (SI), 8th ed.; International Bureau of Weights and Measures: Sèvres, France, 2006; pp 125–26. ISBN 92-822-2213-6, <http://www.bipm.org/utils/common/pdf/si_brochure_8_en.pdf>.
- ↑ Mohr, Peter J.; Taylor, Barry N.; Newell, David B. CODATA Recommended Values of the Fundamental Physical Constants: 2006. Rev. Mod. Phys. 2008, 80 (2), 633–730. doi:10.1103/RevModPhys.80.633, <http://physics.nist.gov/cuu/Constants/codata.pdf>. Direct link to value.
Error creating thumbnail: Unable to save thumbnail to destination |
This page is currently licensed under the Creative Commons Attribution 3.0 Unported license and any later versions of that license. |