carbon 13

noun

Definition of carbon 13

: an isotope of carbon of mass number 13 that constitutes about ¹/₇₀ of natural carbon and is used as a tracer especially in spectroscopy utilizing nuclear magnetic resonance

Examples of carbon 13 in a Sentence

Recent Examples on the Web Chemically, carbon 14 behaves exactly like its stable siblings (carbon 12 and carbon 13), allowing plants to absorb it during photosynthesis and then pass it up the food chain. — Scott Hershberger, Scientific American, "How Do Scientists Determine the Ages of Human Ancestors, Fossilized Dinosaurs and Other Organisms?," 4 Aug. 2020 So researchers compare the amount of carbon 14 with the levels of carbon 12 and carbon 13 to determine how much time has passed since an organism perished. — Scott Hershberger, Scientific American, "How Do Scientists Determine the Ages of Human Ancestors, Fossilized Dinosaurs and Other Organisms?," 4 Aug. 2020 This means that regions that once harbored photosynthetic life contain slightly lower amounts of carbon 13 than sterile areas. — 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 13.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.