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  2. Isotopologue - Wikipedia

    en.wikipedia.org/wiki/Isotopologue

    Altogether, there are 9 different stable water isotopologues, [2] and 9 radioactive isotopologues involving tritium, [3] for a total of 18. However only certain ratios are possible in mixture, due to prevalent hydrogen swapping. The atom(s) of the different isotope may be anywhere in a molecule, so the difference is in the net chemical formula.

  3. Radioactivity in the life sciences - Wikipedia

    en.wikipedia.org/wiki/Radioactivity_in_the_life...

    In the case of the hydrogen isotope tritium (half-life = 12.3 years) and carbon-14 (half-life = 5,730 years), these isotopes derive their importance from all organic life containing hydrogen and carbon and therefore can be used to study countless living processes, reactions, and phenomena.

  4. Tritium - Wikipedia

    en.wikipedia.org/wiki/Tritium

    Tritium (from Ancient Greek τρίτος (trítos) 'third') or hydrogen-3 (symbol T or 3 H) is a rare and radioactive isotope of hydrogen with a half-life of ~12.3 years. The tritium nucleus (t, sometimes called a triton) contains one proton and two neutrons, whereas the nucleus of the common isotope hydrogen-1 (protium) contains one proton and no neutrons, and that of non-radioactive hydrogen ...

  5. Isotopes of hydrogen - Wikipedia

    en.wikipedia.org/wiki/Isotopes_of_hydrogen

    Hydrogen is the only element whose isotopes have different names that remain in common use today: 2 H is deuterium [6] and 3 H is tritium. [7] The symbols D and T are sometimes used for deuterium and tritium; IUPAC ( International Union of Pure and Applied Chemistry ) accepts said symbols, but recommends the standard isotopic symbols 2 H and 3 ...

  6. 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 reaction 14 N + n → 14 C + 1 H. The most ...

  7. 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.

  8. Environmental isotopes - Wikipedia

    en.wikipedia.org/wiki/Environmental_isotopes

    For example, 3 H is a radioactive isotope of hydrogen. It decays into 3 He with a half-life of ~12.3 years. By comparison, stable isotopes do not undergo radioactive decay, and their fixed proportions are measured against exponentially decaying proportions of radioactive isotopes to determine the age of a substance.

  9. Hydrogen isotope biogeochemistry - Wikipedia

    en.wikipedia.org/wiki/Hydrogen_isotope...

    The NMR spectra distinguish hydrogen atoms in different chemical environments (e.g. the order of carbon that hydrogen binds to, adjacent functional groups, and even geminal positions of methylene groups), making it a powerful tool for position-specific isotope analysis. The chemical shift (in frequency units) of 2 H is 6.5x lower than that of 1 H.