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60 Co does not occur naturally on Earth in significant amounts, so 60 Co is synthesized by bombarding a 59 Co target with a slow neutron source. Californium-252, [citation needed] moderated through water, can be used for this purpose, as can the neutron flux in a nuclear reactor.
Naturally occurring cobalt, Co, consists of a single stable isotope, 59 Co (thus, cobalt is a mononuclidic element). Twenty-eight radioisotopes have been characterized; the most stable are 60 Co with a half-life of 5.2714 years, 57 Co (271.811 days), 56 Co (77.236 days), and 58 Co (70.844 days).
Cobalt occurs naturally as only one stable isotope, cobalt-59. Cobalt-60 is a commercially important radioisotope, used as a radioactive tracer and for the production of high-energy gamma rays. Cobalt is also used in the petroleum industry as a catalyst when refining crude oil.
The Earth's crust is one "reservoir" for measurements of abundance. A reservoir is any large body to be studied as unit, like the ocean, atmosphere, mantle or crust. Different reservoirs may have different relative amounts of each element due to different chemical or mechanical processes involved in the creation of the reservoir. [1]: 18
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]
Radioactive decay scheme of 60 Co Gamma emission spectrum of cobalt-60. One example of gamma ray production due to radionuclide decay is the decay scheme for cobalt-60, as illustrated in the accompanying diagram. First, 60 Co decays to excited 60 Ni by beta decay emission of an electron of 0.31 MeV. Then the excited 60 Ni
Liquid water is essential for carbon-based life. Chemical bonding of carbon molecules requires liquid water. [30] Water has the chemical property to make compound-solvent pairing. [31] Water provides the reversible hydration of carbon dioxide. Hydration of carbon dioxide is needed in carbon-based life. All life on Earth uses the same ...
The latter is the fourth-largest constituent of the Earth's atmosphere, while carbon monoxide occurs naturally from various sources (volcanoes, combustion) and has a residence time in the atmosphere of a few months. Hydrogen, which occurs in water, is also classed as an atmophile.