carbon 12


Definition of carbon 12

: an isotope of carbon of mass number 12 that is the most abundant carbon isotope and is used as a standard for measurements of atomic weight

Examples of carbon 12 in a Sentence

Recent Examples on the Web

The key is in the rock’s atomic composition; organisms that use sunlight for energy incorporate a lighter version of carbon, called carbon 12, over the heavier carbon 13. Peter Byrne, Quanta Magazine, "Early Life in Death Valley," 24 Apr. 2014

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'carbon 12.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of carbon 12

1936, in the meaning defined above

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The first known use of carbon 12 was in 1936

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