carbon-14
Sign in to saveCarbon-14, C-14, C or radiocarbon, is a radioactive isotope of carbon with an atomic nucleus containing 6 protons and 8 neutrons. Carbon-14 was discovered on February 27, 1940, by Martin Kamen and Sam Ruben at the University of California Radiation Laboratory in Berkeley, California. Its existence had been suggested by Franz Kurie in 1934. 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.
Key facts
- Isotope.decay_mode1
- Beta
- Isotope.decay_energy1
- 0.1565
- Isotope.num_neutrons
- 8
- Isotope.num_protons
- 6
- Isotope.image
- 碳-14原子核+電子軌道.png
- Isotope.alternate_names
- radiocarbon
- Isotope.mass_number
- 14
- Isotope.abundance
- 1.2 ppt ()
- Isotope.symbol
- C
- Isotope.decay_product
- Nitrogen-14 ()
- Isotope.mass
- 14.0032420
- Isotope.spin
- 0+
via Wikipedia infobox
Article
15 sectionsContents
- Radioactive decay and detection
- Radiocarbon dating
- Origin
- Natural production in the atmosphere
- Other carbon-14 sources
- Formation during nuclear tests
- Emissions from nuclear power plants
- Occurrence
- Dispersion in the environment
- Total inventory
- In fossil fuels
- In the human body
- See also
- References
- Further reading
Carbon-14, C-14, C or radiocarbon, is a radioactive isotope of carbon with an atomic nucleus containing 6 protons and 8 neutrons. Carbon-14 was discovered on February 27, 1940, by Martin Kamen and Sam Ruben at the University of California Radiation Laboratory in Berkeley, California. Its existence had been suggested by Franz Kurie in 1934. 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.
There are three naturally occurring isotopes of carbon on Earth: carbon-12 (C), which makes up 99% of all carbon on Earth; carbon-13 (C), which makes up 1%; and carbon-14 (C), which occurs in trace amounts, making up about 1.2 atoms per 10 atoms of carbon in the atmosphere. C and C are both stable; C is unstable, with half-life years, decaying into nitrogen-14 () through beta decay. Pure carbon-14 would have a specific activity of 62.4 mCi/mmol (2.31 GBq/mmol), or 164.9 GBq/g. The primary natural source of carbon-14 on Earth is cosmic ray action on nitrogen in the atmosphere, and it is therefore a cosmogenic nuclide. Open-air nuclear testing between 1955 and 1980 contributed to this pool, however.