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  2. Carbon-14 - Wikipedia

    en.wikipedia.org/wiki/Carbon-14

    Carbon-14, C-14, 14 C or radiocarbon, is a radioactive isotope of carbon with an atomic nucleus containing 6 protons and 8 neutrons. Its presence in organic matter is the basis of the radiocarbon dating method pioneered by Willard Libby and colleagues (1949) to date archaeological, geological and hydrogeological samples.

  3. Table of nuclides - Wikipedia

    en.wikipedia.org/wiki/Table_of_nuclides

    A table or chart of nuclides is a two-dimensional graph of isotopes of the elements, in which one axis represents the number of neutrons (symbol N) and the other represents the number of protons (atomic number, symbol Z) in the atomic nucleus. Each point plotted on the graph thus represents a nuclide of a known or hypothetical chemical element.

  4. Isotopes of nitrogen - Wikipedia

    en.wikipedia.org/wiki/Isotopes_of_nitrogen

    Nitrogen-13 and oxygen-15 are produced in the atmosphere when gamma rays (for example from lightning) knock neutrons out of nitrogen-14 and oxygen-16: 14 N + γ → 13 N + n 16 O + γ → 15 O + n. The nitrogen-13 produced as a result decays with a half-life of 9.965(4) min to carbon-13, emitting a positron.

  5. 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

  6. Carbon - Wikipedia

    en.wikipedia.org/wiki/Carbon

    Carbon (from Latin carbo ' coal ') is a chemical element; it has symbol C and atomic number 6. It is nonmetallic and tetravalent—meaning that its atoms are able to form up to four covalent bonds due to its valence shell exhibiting 4 electrons. It belongs to group 14 of the periodic table. [13] Carbon makes up about 0.025 percent of Earth's ...

  7. Bohr model - Wikipedia

    en.wikipedia.org/wiki/Bohr_model

    In atomic physics, the Bohr model or Rutherford–Bohr model was the first successful model of the atom. Developed from 1911 to 1918 by Niels Bohr and building on Ernest Rutherford 's nuclear model , it supplanted the plum pudding model of J. J. Thomson only to be replaced by the quantum atomic model in the 1920s.

  8. List of chemical elements - Wikipedia

    en.wikipedia.org/wiki/List_of_chemical_elements

    It is a tabular arrangement of the elements by their chemical properties that usually uses abbreviated chemical symbols in place of ... Carbon [q] 14 2 p-block 12.011 ...

  9. Atom - Wikipedia

    en.wikipedia.org/wiki/Atom

    A given atom has an atomic mass approximately equal (within 1%) to its mass number times the atomic mass unit (for example the mass of a nitrogen-14 is roughly 14 Da), but this number will not be exactly an integer except (by definition) in the case of carbon-12. [67] The heaviest stable atom is lead-208, [59] with a mass of 207.976 6521 Da. [68]