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Nitrogen-14 is the source of naturally-occurring, radioactive, carbon-14. Some kinds of cosmic radiation cause a nuclear reaction with nitrogen-14 in the upper atmosphere of the Earth, creating carbon-14, which decays back to nitrogen-14 with a half-life of 5700(30) years.
Nitrogen is a chemical element; it has symbol N and atomic number 7. ... Nitrogen has two stable isotopes: 14 N and 15 N. The first is much more common, making up 99. ...
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.
[5] [12] These cosmic rays generate neutrons as they travel through the atmosphere which can strike nitrogen-14 (14 N) atoms and turn them into 14 C. [5] The following nuclear reaction is the main pathway by which 14 C is created: n + 14 7 N → 14 6 C + p. where n represents a neutron and p represents a proton. [13] [14] [note 3] Once produced ...
When the cycle is run to equilibrium, the ratio of the carbon-12/carbon-13 nuclei is driven to 3.5, and nitrogen-14 becomes the most numerous nucleus, regardless of initial composition. During a star's evolution, convective mixing episodes moves material, within which the CNO cycle has operated, from the star's interior to the surface, altering ...
An example of electron emission (β − decay) is the decay of carbon-14 into nitrogen-14 with a half-life of about 5,730 years: 14 6 C → 14 7 N + e − + ν e. In this form of decay, the original element becomes a new chemical element in a process known as nuclear transmutation.
[citation needed] The 14 N (n,p) 14 C nuclear reaction is responsible for most of the radiation dose delivered to the human body by thermal neutrons – these thermal neutrons are absorbed by the nitrogen 14 N in proteins, causing a proton to be emitted; the emitted proton deposits its kinetic energy over a very short distance in the body ...
Examples include carbon-14, nitrogen-15, and oxygen-16 in the table above. Isobars are nuclides with the same number of nucleons (i.e. mass number) but different numbers of protons and neutrons. Isobars neighbor each other diagonally from lower-left to upper-right. Examples include carbon-14, nitrogen-14, and oxygen-14 in the table above.