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Carbon dating definition chemistry
Radiocarbon decays slowly in a living organism, and the amount lost is continually replenished as long as the organism takes in air or food.
Carbon-14 has a half-life of 5,730 ± 40 years—, half the amount of the radioisotope present at any given time will undergo spontaneous disintegration during the succeeding 5,730 years.
Because carbon-14 decays at this constant rate, an estimate of the date at which an organism died can be made by measuring the amount of its residual radiocarbon.
So, a carbon atom might have six neutrons, or seven, or possibly eight—but it would always have six protons.
An “isotope” is any of several different forms of an element, each having different numbers of neutrons.
The carbon-14 method was developed by the American physicist Willard F. It has proved to be a versatile technique of dating fossils and archaeological specimens from 500 to 50,000 years old.
The method is widely used by Pleistocene geologists, anthropologists, archaeologists, and investigators in related fields.
For example, all carbon atoms have 6 protons, all atoms of nitrogen have 7 protons, and all oxygen atoms have 8 protons.
The number of neutrons in the nucleus can vary in any given type of atom.
Carbon-14 is continually formed in nature by the interaction of neutrons with nitrogen-14 in the Earth’s atmosphere; the neutrons required for this reaction are produced by cosmic rays interacting with the atmosphere.
Radiocarbon present in molecules of atmospheric carbon dioxide enters the biological carbon cycle: it is absorbed from the air by green plants and then passed on to animals through the food chain.