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carbon 12
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noun
the isotopic carbon atom that comprises 99 percent of naturally occurring carbon, and that since 1961 has been used as the standard for atomic weight by representing a unit of 12.00000.
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Also car·bon-12 [kahr-buhn-twelv]. /ˈkɑr bənˈtwɛlv/.
Origin of carbon 12
First recorded in 1940–45
Words nearby carbon 12
carbo load, carbo-loading, Carboloy, car bomb, carbon, carbon 12, carbon 13, carbon 14, carbon-14 dating, carbonaceous, carbonade
Dictionary.com Unabridged
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Scientific definitions for carbon 12
carbon 12
A stable isotope of carbon, having six protons and six neutrons in the nucleus. Carbon 12 makes up most naturally occurring carbon.
The American Heritage® Science Dictionary
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