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  2. Carbon-13 - Wikipedia

    en.wikipedia.org/wiki/Carbon-13

    Carbon-13 has a non-zero spin quantum number of ⁠ 1 / 2 ⁠, and hence allows the structure of carbon-containing substances to be investigated using carbon-13 nuclear magnetic resonance. The carbon-13 urea breath test is a safe and highly accurate diagnostic tool to detect the presence of Helicobacter pylori infection in the stomach. [4] The ...

  3. 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

  4. Table of nuclides - Wikipedia

    en.wikipedia.org/wiki/Table_of_nuclides

    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. Examples include carbon-12, carbon-13, and carbon-14 in the table above.

  5. 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 ...

  6. Isotope - Wikipedia

    en.wikipedia.org/wiki/Isotope

    For example, carbon-12, carbon-13, and carbon-14 are three isotopes of the element carbon with mass numbers 12, 13, and 14, respectively. The atomic number of carbon is 6, which means that every carbon atom has 6 protons so that the neutron numbers of these isotopes are 6, 7, and 8 respectively.

  7. List of compounds with carbon number 13 - Wikipedia

    en.wikipedia.org/wiki/List_of_compounds_with...

    This is a partial list of molecules that contain 13 carbon atoms. ... Synonyms CAS number; C 13 H 5 Cl 5 O 3: pentachlorophenyl salicylate: 36994-69-1 C 13 H 7 MoNO 5:

  8. Nuclide - Wikipedia

    en.wikipedia.org/wiki/Nuclide

    A nuclide is a species of an atom with a specific number of protons and neutrons in the nucleus, for example carbon-13 with 6 protons and 7 neutrons. The nuclide concept (referring to individual nuclear species) emphasizes nuclear properties over chemical properties, while the isotope concept (grouping all atoms of each element) emphasizes ...

  9. Carbon-13 nuclear magnetic resonance - Wikipedia

    en.wikipedia.org/wiki/Carbon-13_nuclear_magnetic...

    The major isotope of carbon, the 12 C isotope, has a spin quantum number of zero and so is not magnetically active and therefore not detectable by NMR. 13 C, with a spin quantum number of 1/2, is not abundant (1.1%), whereas other popular nuclei are 100% abundant, e.g. 1 H, 19 F, 31 P.