atomic mass unit

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atomic mass unit

atomic mass unit or amu, in chemistry and physics, unit defined as exactly 1/12 the mass of an atom of carbon-12, the isotope of carbon with six protons and six neutrons in its nucleus. One amu is equal to approximately 1.66 × 10 ^-24 grams.

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"atomic mass unit." The Columbia Encyclopedia, Sixth Edition. 2008. Encyclopedia.com. 22 Dec. 2009 <http://www.encyclopedia.com>.

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atomic mass unit

World Encyclopedia | 2005 | Â© World Encyclopedia 2005, originally published by Oxford University Press 2005. (Hide copyright information) Copyright

atomic mass unit (amu) Unit of mass used to compare relative atomic masses, defined as 1/12th the mass of the most abundant isotope of carbon, carbon-12 (6 electrons, 6 protons, and 6 neutrons). One amu is equal to 1.66033 × 10⁻²⁷ kg.

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amu

The Oxford Pocket Dictionary of Current English | 2009 | © The Oxford Pocket Dictionary of Current English 2009, originally published by Oxford University Press 2009. (Hide copyright information) Copyright

amu • abbr. atomic mass unit.

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