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  2. Potassium-40 - Wikipedia

    en.wikipedia.org/wiki/Potassium-40

    The decay of 40 K in Earth's mantle ranks third, after 232 Th and 238 U, in the list of sources of radiogenic heat. Less is known about the amount of radiogenic sources in Earth's outer and inner core, which lie below the mantle. It has been proposed, though, that significant core radioactivity (1–2 TW) may be caused by high levels of U, Th ...

  3. Isotopes of potassium - Wikipedia

    en.wikipedia.org/wiki/Isotopes_of_potassium

    19 K) has 25 known isotopes from 34 K to 57 K as well as 31 K, as well as an unconfirmed report of 59 K. [3] Three of those isotopes occur naturally: the two stable forms 39 K (93.3%) and 41 K (6.7%), and a very long-lived radioisotope 40 K (0.012%) Naturally occurring radioactive 40 K decays with a half-life of 1.248×10 9 years. 89% of those ...

  4. Isotopic labeling - Wikipedia

    en.wikipedia.org/wiki/Isotopic_labeling

    The compounds produced using stable isotopes are either specified by the percentage of labeled isotopes (that is, 30% uniformly labeled 13 C glucose contains a mixture that is 30% labeled with 13 carbon isotope and 70% naturally labeled carbon) or by the specifically labeled carbon positions on the compound (that is, 1-13 C glucose which is ...

  5. Table of nuclides - Wikipedia

    en.wikipedia.org/wiki/Table_of_nuclides

    The darker more stable isotope region departs from the line of protons (Z) = neutrons (N), as the element number Z becomes larger. Isotopes are nuclides with the same number of protons but differing numbers of neutrons; that is, they have the same atomic number and are therefore the same chemical element. Isotopes neighbor each other vertically.

  6. List of particles - Wikipedia

    en.wikipedia.org/wiki/List_of_particles

    "Isotopes" are nuclides which have the same number of protons but differing numbers of neutrons. Conversely, "isotones" are nuclides which have the same number of neutrons but differing numbers of protons. "Isobars" are nuclides which have the same total number of nucleons but which differ in the number of each type of nucleon.

  7. List of nuclides - Wikipedia

    en.wikipedia.org/wiki/List_of_nuclides

    The mass of the nuclide (in daltons) is A (m n − E / k) where E is the energy, m n is 1.008664916 Da and k = 931.49410242 the conversion factor between MeV and daltons. half-life column The main column shows times in seconds (31,556,926 seconds = 1 tropical year ); a second column showing half-life in more usual units (year, day) is also ...

  8. Category:Lists of isotopes by element - Wikipedia

    en.wikipedia.org/wiki/Category:Lists_of_isotopes...

    Pages in category "Lists of isotopes by element" The following 122 pages are in this category, out of 122 total. This list may not reflect recent changes. A.

  9. 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 ...