The least abundant of the two stable isotopes of carbon, 136C, having six protons and seven neutrons(noun)
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Use "carbon-13" in a sentence
"There’s also carbon-13, which is too short-lived to bother with, and carbon-14 which is rare but not too rare to be useful for dating relatively young organic samples, as we shall see."
"Deriving their energy from the sun and their carbon from carbon dioxide in the air, any given type of plant will typically contain a similar ratio of carbon-12 to carbon-13 as another plant of the same type."
"And Prototaxites displayed a much wider variation in its ratio of carbon-12 to carbon-13 content than would be expected in any plant."