atomic mass unit

atomic mass unit

noun Physics.
1.
Also called dalton. a unit of mass, equal to 1/12 (0.0833) the mass of the carbon-12 atom and used to express the mass of atomic and subatomic particles.
2.
(formerly) a unit of mass, equal to 1/16 (0.0625) the mass of an oxygen atom having atomic mass 16. Abbreviation: amu, AMU

Origin:
1950–55

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World English Dictionary
atomic mass unit
 
n
amu, unified atomic mass unit, Also called: dalton a unit of mass used to express atomic and molecular weights that is equal to one twelfth of the mass of an atom of carbon-12. It is equivalent to 1.66 × 10--27 kg

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American Heritage
Medical Dictionary

atomic mass unit n.
Abbr. amu
A unit of mass equal to 1/12 the mass of an atom of carbon 12, which is assigned a mass of 12. Also called dalton.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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Science Dictionary
atomic mass unit  
A unit of mass equal to 1/12 the mass of an atom of the most common isotope of carbon (carbon 12), which is assigned a mass of 12 and has a value of 1.660 × 10-24 grams. A hydrogen atom has a mass of 1 atomic mass unit since its mass is 1/12 the mass of carbon 12. Also called dalton.
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Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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