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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.
The equation for the radioactive decay of 14 C is: [17] 14 6 C → 14 7 N + e − + ν e. By emitting a beta particle (an electron, e −) and an electron antineutrino (ν e), one of the neutrons in the 14 C nucleus changes to a proton and the 14 C nucleus reverts to the stable (non-radioactive) isotope 14 N. [18]
In contrast, intrinsic radiolabeling of a molecule can be done without altering its structure in any way. For example, substituting a H-3 for a hydrogen atom or C-14 for a carbon atom does not change the conformation, structure, or any other property of the molecule, it's just switching forms of the same atom.
[citation needed] Silicon biochemistry (Organosilicon) Alternative biochemistry Silicon-based life Like carbon, silicon can create molecules that are sufficiently large to carry biological information; however, the scope of possible silicon chemistry is far more limited than that of carbon. [citation needed] Silicon dioxide biochemistry
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
A large fraction of the chemical elements that occur naturally on the Earth's surface are essential to the structure and metabolism of living things. Four of these elements (hydrogen, carbon, nitrogen, and oxygen) are essential to every living thing and collectively make up 99% of the mass of protoplasm. [1]
Records show that from the 1940s through the 1960s, it was not uncommon for local hospitals, labs and other industrial operations to dispose barrels of tritium, carbon-14 and other similar waste ...
The effects of radiation on cells has been found to be dependent on the dosage of the radiation, the location of the cell in regards to tissue, and whether the cell is a somatic or germ line cell. Generally, ionizing radiation appears to reduce methylation of DNA in cells.