Superliminal achievement guide12/11/2023 ![]() During the detonation, the strong gamma emitter would be formed, through which the environment would become more contaminated than by the nuclear explosion alone. The formation of 60Co from 59Co under neutron radiation could potentially also be used to enhance the effect of nuclear weapons that produce neutron radiation by being coated with cobalt (cobalt bomb). 59Co pellets are exposed to neutron flux in nuclear reactors to produce larger quantities. Spontaneous fission sources such as 252Cf serve as the source of neutron for the production of smaller quantities. In medicine, other isotopes such as 57Co or 58Co can be used as tracers.Ħ0Co is exclusively obtained artificially by neutron activation from 59Co. For this reason, 60Co is used as a source of gamma radiation for sterilizing or preserving food, for material examination (radiographic examination) and in cancer therapy ("cobalt gun"). The most long-lived of the unstable isotopes is 60Co (Cobalt-60, Spin 5 +), with a half-life of 5,27 years under beta decay, first in an excited state of 60Ni (Spin 4 +) and then emitting gamma radiation (two energy 1,17 and 1,33 MeV) into the ground state (spin 0 +) of this nuclide decays. ![]() The main application of 57Co is Mössbauer spectroscopy to distinguish bivalent and trivalent iron. The gamma radiation emitted during the transition to the ground state of the daughter nucleus has an energy of 122,06 keV (85,6%) and 14,4 keV (9,16%). The nuclide 57Co decays via electron capture to 57Fe. This isotope can be examined by NMR spectroscopy. The element is therefore one of the 22 pure elements. Natural cobalt consists entirely of the isotope 59Co. There are a total of 30 isotopes and 18 other core isomers between 47Co and 77Co known. In this, unlike covalent compounds, the oxidation state + III is more abundant and stable than + II. Cobalt forms a variety of mostly colored complexes. However, the oxidation states -I, 0, + I, + II, + III, + IV and + V are also represented in compounds. In compounds, it occurs predominantly in the oxidation states + II and + III. Cobalt is one of the non-noble elements with a normal potential of -0,277 V. In chemical behavior it is similar to iron and nickel, resistant to air by passivation it is only dissolved by oxidizing acids. This peculiarity exists between argon and potassium as well as between tellurium and iodine. The hcp modification (α-cobalt, historically ε-cobalt) is more stable at lower temperatures and changes at about 450 ° C into the fcc modification (β-cobalt, historically α-cobalt).Īs a typical metal it conducts heat and electricity well, the electrical conductivity is 26 percent of that of copper.Ī special feature is the atomic mass of the naturally occurring cobalt with 58,93 it is larger than the average atomic mass of nickel with 58,69, the next element in the periodic table. Cobalt occurs in two modifications: a hexagonal-dense (hcp) crystal structure in the space group P63 / mmc (space group number 194) with the lattice parameters a = 250,7 pm and c = 406,9 pm and two formula units per unit cell and a cubic face centered Form (fcc) with the grid parameter a = 354,4 pm. It is ferromagnetic with a Curie temperature of 1150 ° C. Magnetite crystal structure of α-Co, a = 250,7 pm, c = 406,9 pmĬobalt is a steel gray, very tough heavy metal with a density of 8,89 g / cm³. Magnetization curves of 9 ferromagnetic materials.1. 1780 discovered Torbern Olof Bergman exploring the properties that cobalt is an element. 1735 discovered the Swedish chemist Georg Brandt in the preparation of cobalt salts the hitherto unknown metal, described its properties and gave it its present name. These ores were then occupied by the miners with nicknames such as nickel, tungsten (such as "wolf foam", Latin lupi spuma) and just Kobolderz, so cobalt. In addition to cobalt, these were also tungsten and nickel ores. Supposedly goblins had eaten the precious silver and eliminated in its place worthless silver ores. However, since they could not be processed and because of the arsenic content on heating gave off bad odors, they were considered bewitched. In the Middle Ages, they were often considered valuable silver and copper ores. Subgroup or iron-platinum group.Ĭobalt salts and cobalt compounds have been known for a long time and were used as cobalt blue predominantly for coloring glass and ceramics. In the older counting it counts to the 8. Group or cobalt group of the periodic table. Cobalt is a ferromagnetic transition metal from the 9. Cobalt prices, history, occurrence, extraction and useĬobalt (chemical jargon, Latin cobaltum, standard cobalt, named Cobalt Rex from the first describer after Cobalt ore) is a chemical element with the elementary symbol Co and atomic number 27.
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