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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.
Radiocarbon dating helped verify the authenticity of the Dead Sea scrolls.. Radiocarbon dating (also referred to as carbon dating or carbon-14 dating) is a method for determining the age of an object containing organic material by using the properties of radiocarbon, a radioactive isotope of carbon.
Martin David Kamen (August 27, 1913, Toronto – August 31, 2002, Montecito, California) was an American chemist who, together with Sam Ruben, co-discovered the synthesis of the isotope carbon-14 on February 27, 1940, at the University of California Radiation Laboratory, Berkeley. [1]
In 1939, Serge Korff had discovered that cosmic rays generated neutrons in the upper atmosphere. These interact with nitrogen-14 in the air to produce carbon-14: [25] [26] 1 n + 14 N → 14 C + 1 p. The half-life of carbon-14 is 5,730±40 years. [27]
Carbon-14, though, is continuously created through collisions of neutrons generated by cosmic rays with nitrogen in the upper atmosphere and thus remains at a near-constant level on Earth. The carbon-14 ends up as a trace component in atmospheric carbon dioxide (CO 2). [31] A carbon-based life form acquires carbon during its lifetime.
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 ...
At 8 am, February 27, 1940, Ruben demonstrated unequivocally that the radioactivity was from carbon-14. [citation needed] Use of carbon-14 in tracer experiments was hindered by the difficulty measuring the weak beta emission of the radioactive decay and by the onset of World War II that shut off production of the isotope.
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