Two other isotopes of cobalt, cobalt-57 and cobalt-58, are used for the same purpose.Ĭobalt-60 is also used to treat cancer. This test is a method for determining whether a person's body is making and using vitaminB 12 properly. For example, it is used in a test known as the Schilling test. In medicine, it is used to find and treat diseases. These particles stick in the atoms and make them radioactive.Ĭobalt-60 is one of the most widely used of all radioactive isotopes. Radioactive isotopes are produced when very small particles are fired at atoms. A radioactive isotope is one that breaks apart and gives off some form of radiation. Ten radioactive isotopes of cobalt are known also. Neutrons in the atom of any one element can vary. The number of protons determines the element, but the number of The mass number represents the number of protons plus neutrons in the nucleus of an atom of the element. The number written to the right of the element's name is the mass number. Isotopes differ from each other according to their mass number. Isotopes are two or more forms of an element. There is only one naturally occurring isotope of cobalt, cobalt-59. The word cobalt, from the German word Kobold, meaning "goblin" or "evil spirit," was used by miners to describe a mineral that was very difficult to mine and was damaging to their health. The major suppliers of cobalt in the world are Zambia, Canada, Russia, Australia, Zaire, and Cuba. ![]() ![]() The most common ores of cobalt are cobaltite, smaltite, chloranthite, and linnaeite. This places it in the upper third of elements according to their abundance in the Earth's crust. Occurrence in natureĬobalt is a relatively abundant element at about 10 to 30 parts per million. It does not react with water at room temperatures. It reacts with most acids to produce hydrogen gas. It combines slowly with oxygen in the air, but does not catch fire and burn unless it is in a powder form. Chemical propertiesĬobalt is a moderately reactive element. The density is 8.9 grams per cubic centimeter. The melting point of cobalt metal is 1,493 ☌ (2,719 ☏), and the boiling point is about 3,100 ☌ (5,600 ☏). The mixture has properties different from those of the individual metals. An alloy is made by melting and mixing two or more metals. The magnetic properties of cobalt are even more obvious in alloys. Malleable means capable of being hammered into thin sheets.Ĭobalt is one of only three naturally occurring magnetic metals. Ductile means capable of being drawn into thin wires. It is ductile, but only moderately malleable. Physical propertiesĬobalt is a hard, gray metal that looks much like iron and nickel. The name chosen was a version of the original German term, Kobold. (Copper and cobalt compounds had long been confused with each other.) Eventually, Brandt was given credit for the discovery of the element. He showed that its compounds were a much deeper blue than copper compounds. The gas that affected the miners was arsenic trioxide (As 4O 6), which often occurs with cobalt in nature.Īt first, chemists were skeptical about Brandt's claims of a new element, but he continued his research on the mineral. When the mineral was heated, it gave off an offensive gas that caused illness. In German, the word Kobold means "goblin" or "evil spirit." The term was used by miners to describe a mineral that was very difficult to mine and was damaging to their health. The word cobalt may have been first used near the end of the fifteenth century. Cobalt minerals were especially prized for their rich blue color. Craftsmen used materials from the earth to color glass, pottery, glazes, and other materials. Discovery and namingĬobalt dyes have been used for centuries. Superalloys are used in jet engine parts and gas turbines. Superalloys are resistant to corrosion (rusting) and retain their properties at high temperatures. Superalloys primarily consist of iron, cobalt, or nickel, with small amounts of other metals, such as chromium, tungsten, aluminum, and titanium. The most important application is in the production of superalloys. The United States has to import all the cobalt it uses. Cobalt is located between iron and nickel and shares many chemical and physical properties with these two elements. ![]() The periodic table is a chart that shows how chemical elements are related to each other. Brandt demonstrated that the pigment contained a new element, later named cobalt.Ĭobalt is a transition metal, one of several elements found in Rows 4 through 7 between Groups 2 and 13 in the periodic table. In 1735, Swedish chemist Georg Brandt (1694-1768) analyzed a dark blue pigment found in copper ore. The compounds were used to color glass and glazes blue. Humans have been using compounds of cobalt since at least 1400 b.c. Note: This article, originally published in 1998, was updated in 2006 for the eBook edition.
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