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  2. Natural abundance - Wikipedia

    en.wikipedia.org/wiki/Natural_abundance

    In physics, natural abundance (NA) refers to the abundance of isotopes of a chemical element as naturally found on a planet. The relative atomic mass (a weighted average, weighted by mole-fraction abundance figures) of these isotopes is the atomic weight listed for the element in the periodic table. The abundance of an isotope varies from ...

  3. Isotopes of sulfur - Wikipedia

    en.wikipedia.org/wiki/Isotopes_of_sulfur

    Sulfur (16 S) has 23 known isotopes with mass numbers ranging from 27 to 49, four of which are stable: 32 S (95.02%), 33 S (0.75%), 34 S (4.21%), and 36 S (0.02%). The preponderance of sulfur-32 is explained by its production from carbon-12 plus successive fusion capture of five helium-4 nuclei, in the so-called alpha process of exploding type II supernovas (see silicon burning).

  4. 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

  5. Isotopes of hydrogen - Wikipedia

    en.wikipedia.org/wiki/Isotopes_of_hydrogen

    1 H (atomic mass 1.007 825 031 898 (14) Da) is the most common hydrogen isotope, with an abundance of >99.98%. Its nucleus consists of only a single proton, so it has the formal name protium. The proton has never been observed to decay, so 1 H is considered a stable isotope.

  6. Isotopes of boron - Wikipedia

    en.wikipedia.org/wiki/Isotopes_of_boron

    All other isotopes have half-lives shorter than 17.35 ms. Those isotopes with mass below 10 decay into helium (via short-lived isotopes of beryllium for 7 B and 9 B) while those with mass above 11 mostly become carbon. A chart showing the abundances of the naturally occurring isotopes of boron.

  7. Isotopes of chlorine - Wikipedia

    en.wikipedia.org/wiki/Isotopes_of_chlorine

    Chlorine (17 Cl) has 25 isotopes, ranging from 28 Cl to 52 Cl, and two isomers, 34m Cl and 38m Cl. There are two stable isotopes, 35 Cl (75.8%) and 37 Cl (24.2%), giving chlorine a standard atomic weight of 35.45. The longest-lived radioactive isotope is 36 Cl, which has a half-life of 301,000 years. All other isotopes have half-lives under 1 ...

  8. Isotopes of lead - Wikipedia

    en.wikipedia.org/wiki/Isotopes_of_lead

    The relative abundances of the four stable isotopes are approximately 1.5%, 24%, 22%, and 52.5%, combining to give a standard atomic weight (abundance-weighted average of the stable isotopes) of 207.2(1). Lead is the element with the heaviest stable isotope, 208 Pb.

  9. Isotopes of rubidium - Wikipedia

    en.wikipedia.org/wiki/Isotopes_of_rubidium

    Rubidium (37 Rb) has 36 isotopes, with naturally occurring rubidium being composed of just two isotopes; 85 Rb (72.2%) and the radioactive 87 Rb (27.8%). 87 Rb has a half-life of 4.92 × 10 10 years. It readily substitutes for potassium in minerals, and is therefore fairly widespread.