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  2. Isotopes of carbon - Wikipedia

    en.wikipedia.org/wiki/Isotopes_of_carbon

    Carbon (6 C) has 14 known isotopes, from 8 C to 20 C as well as 22 C, of which 12 C and 13 C are stable.The longest-lived radioisotope is 14 C, with a half-life of 5.70(3) × 10 3 years. . This is also the only carbon radioisotope found in nature, as trace quantities are formed cosmogenically by the reactio

  3. List of elements by stability of isotopes - Wikipedia

    en.wikipedia.org/wiki/List_of_elements_by...

    The darker more stable isotope region departs from the line of protons (Z) = neutrons (N), as the element number Z becomes larger. This is a list of chemical elements by the stability of their isotopes. Of the first 82 elements in the periodic table, 80 have isotopes considered to be stable. [1] Overall, there are 251 known stable isotopes in ...

  4. δ13C - Wikipedia

    en.wikipedia.org/wiki/Δ13C

    Foraminifera samples. In geochemistry, paleoclimatology, and paleoceanography δ 13 C (pronounced "delta thirteen c") is an isotopic signature, a measure of the ratio of the two stable isotopes of carbon— 13 C and 12 C—reported in parts per thousand (per mil, ‰). [1]

  5. Carbon-12 - Wikipedia

    en.wikipedia.org/wiki/Carbon-12

    Carbon-12 (12 C) is the most abundant of the two stable isotopes of carbon (carbon-13 being the other), amounting to 98.93% of element carbon on Earth; [1] its abundance is due to the triple-alpha process by which it is created in stars.

  6. Carbon-13 - Wikipedia

    en.wikipedia.org/wiki/Carbon-13

    Bulk carbon-13 for commercial use, e.g. in chemical synthesis, is enriched from its natural 1% abundance. Although carbon-13 can be separated from the major carbon-12 isotope via techniques such as thermal diffusion, chemical exchange, gas diffusion, and laser and cryogenic distillation, currently only cryogenic distillation of methane (boiling point −161.5°C) or carbon monoxide (b.p. − ...

  7. Carbon - Wikipedia

    en.wikipedia.org/wiki/Carbon

    Isotopes of carbon are atomic nuclei that contain six protons plus a number of neutrons (varying from 2 to 16). Carbon has two stable, naturally occurring isotopes. [69] The isotope carbon-12 (12 C) forms 98.93% of the carbon on Earth, while carbon-13 (13 C) forms the remaining 1.07%. [69]

  8. List of radioactive nuclides by half-life - Wikipedia

    en.wikipedia.org/wiki/List_of_radioactive...

    This is a list of radioactive nuclides (sometimes also called isotopes), ordered by half-life from shortest to longest, in seconds, minutes, hours, days and years. Current methods make it difficult to measure half-lives between approximately 10 −19 and 10 −10 seconds.

  9. Isotope geochemistry - Wikipedia

    en.wikipedia.org/wiki/Isotope_geochemistry

    Oxygen has three stable isotopes, 16 O, 17 O, and 18 O. Oxygen ratios are measured relative to Vienna Standard Mean Ocean Water (VSMOW) or Vienna Pee Dee Belemnite (VPDB). [2] Variations in oxygen isotope ratios are used to track both water movement, paleoclimate, [1] and atmospheric gases such as ozone and carbon dioxide. [5]