carbon-13

isotope

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June 22, 2026

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Carbon-13 (¹³C) is a stable isotope of carbon that makes up about 1.07% of natural carbon. It is distinct from the more abundant carbon-12 (¹²C), which constitutes 98.93% of natural carbon. Carbon-13 is utilized as a tracer in spectroscopy, particularly in nuclear magnetic resonance (NMR). Its nuclear spin allows it to respond to NMR spectrometers, aiding in the investigation of molecular structures in covalently bonded compounds. Additionally, carbon-13 can be used as a label in compounds analyzed by mass spectrometry.123

Another significant carbon isotope is carbon-14 (¹⁴C), which is radioactive and has a half-life of approximately 5,730 years. Carbon-14 is crucial for radiocarbon dating, a method used to determine the age of fossils and archaeological specimens.415

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carbon
Nuclear properties
…percent of natural carbon) and carbon-13 (1.07 percent); 14 radioactive isotopes are known, of which the longest-lived is carbon-14, which has a half-life of 5,730 ± 40 years.
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…percent of natural carbon) and carbon-13 (1.07 percent); 14 radioactive isotopes are known, of which the longest-lived is carbon-14, which has a half-life of 5,730 ± 40 years.
Read More