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Cobalt-64
Naturally occurring cobalt (Co) consists of a single stable isotope, Co. Twenty-eight radioisotopes have been characterized; the most stable are Co with a half-life of 5.2714 years, Co (271.8 days), Co (77.27 days), and Co (70.86 days). All other isotopes have half-lives less than 18 hours and most of these have half-lives less than 1 second. This element also has 11 meta states, all of which have half-lives less than 15 minutes. The isotopes of cobalt range in atomic weight from Co to Co. The main decay mode for isotopes with atomic mass less than that of the stable isotope, Co, is electron capture and the main mode of decay for those of greater than 59 atomic mass units is beta decay. The main decay products before Co are iron isotopes and the main products after are nickel isotopes. Radioactive isotopes can be produced by various nuclear reactions. For example, Co is produced by cyclotron irradiation of iron. The main reaction is the (d,n) reaction Fe + H → n + Co. List ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cobalt
Cobalt is a chemical element with the symbol Co and atomic number 27. As with nickel, cobalt is found in the Earth's crust only in a chemically combined form, save for small deposits found in alloys of natural meteoric iron. The free element, produced by reductive smelting, is a hard, lustrous, silver-gray metal. Cobalt-based blue pigments ( cobalt blue) have been used since ancient times for jewelry and paints, and to impart a distinctive blue tint to glass, but the color was for a long time thought to be due to the known metal bismuth. Miners had long used the name ''kobold ore'' (German for ''goblin ore'') for some of the blue-pigment-producing minerals; they were so named because they were poor in known metals, and gave poisonous arsenic-containing fumes when smelted. In 1735, such ores were found to be reducible to a new metal (the first discovered since ancient times), and this was ultimately named for the ''kobold''. Today, some cobalt is produced specifically from one of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
