Cobalt

=**Cobalt:**=

**Atomic number: 27**
 * Symbol: Co**
 * Atomic mass: 58.933195**
 * Melting Point:** 1768 K (1495°C or 2723°F)
 * Boiling Point:** 3200 K (2927°C or 5301°F)
 * Density:** 8.86 grams per cubic centimeter
 * Phase at Room Temperature:** Solid
 * Element Classification:** Metal
 * Period Number:** 4
 * Group Number:** 9


 * Number of Energy Levels:** 4
 * First Energy Level:**2
 * Second Energy Level:**8
 * Third Energy Level:**15
 * Fourth Energy Level:**2

Isotopes

 * ** Isotope ** || ** Half Life ** ||
 * Co-56 || 77.3 days ||
 * Co-57 || 271.8 days ||
 * Co-58 || 70.9 days ||
 * Co-58m || 9.1 hours ||
 * Co-59 || Stable ||
 * Co-60 || 5.3 years ||
 * Co-60m || 10.5 minutes ||
 * Co-61 || 1.7 hours ||

Facts

 * Date of Discovery:** 1737
 * Discoverer:** George Brandt
 * Name Origin:** From the German word //kobalt// or //kobold// (evil spirit)
 * Uses:** magnets, ceramics, special glasses
 * Obtained From:** arsenic, oxygen, sulfur, cobaltine

__Characteristics:__ Cobalt is a transition metal that is a hard, silver-gray metal. It is not found in nature, but compounds of Cobalt are commonly found in nature. It is found in small amounts in most rocks, soil, plants, and animals. When found in these examples, it is often confused for nickel. Cobalt has a hexagonal crystal structure.

__History:__ Cobalt was discovered around 1735 by scientist Georg Brantd. He discovered it when examining other metals. He was specifically looking for proof of a new element that had the ability to color glass blue, when he came across cobalt. Due to the visible differences from other metals, Brantd referred to Cobalt as a "semi-metal." Cobalt has been used for centuries in glass, jewelry, and pottery. This is due to the rich, blue pigment it contains.



__ Uses of Cobalt: __ Cobalt is usually recovered as a byproduct of mining and refining nickel, silver, lead, copper and iron. Cobalt is widely used to form alloys. Alnico, an alloy consisting of aluminum, nickel and cobalt is used to make powerful permanent magnets. Stellite alloys, which contain cobalt, chromium and tungsten, are used to make high-speed and high temperature cutting tools and dyes. Cobalt is also used to make alloys for jet engines and gas turbines, magnetic steels and some types of stainless steels. Cobalt-60, a radioactive isotope of cobalt, is an important source of gamma rays and is used to treat some forms of cancer and as a medical tracer. Cobalt blue is used to as a preventive measure and treatment for radiation poisoning. Cobalt compounds have been used for centuries to color porcelain, glass, pottery, tile, enamel and even cobalt boats. Some of these compounds are known as: cobalt blue, ceruleum, new blue, smalt, cobalt yellow and cobalt green. In addition to being used as a dye, cobalt is also important to human nutrition as it is an essential part of vitamin B 12.

Sources: []

Cobalt compounds have been used for centuries to impart a rich blue color to glass, glazes and ceramics. Cobalt has been detected in Egyptian sculpture and Persian jewelry from the third millennium BC, in the ruins of Pompeii (destroyed in 79 AD), and in China dating from the Tang dynasty (618–907 AD) and the Ming dynasty (1368–1644 AD). Cobalt has been used to color glass since the Bronze Age. The excavation of the Uluburun shipwreck yielded an ingot of blue glass, which was cast during the 14th century BC. Blue glass items from Egypt are colored with copper, iron, or cobalt. The oldest cobalt-colored glass was from the time of the Eighteenth dynasty in Egypt (1550–1292 BC). The location where the cobalt compounds were obtained is unknown.
 * Symbol:** Co **Atomic Number:** 27 **Atomic Mass:** 58.9332 amu **Melting Point:** 1495.0 °C (1768.15 K, 2723.0 °F) **Boiling Point:** 2870.0 °C (3143.15 K, 5198.0 °F) **Number of Protons/Electrons:** 27 **Number of Neutrons:** 32 **Classification:** Transition Metal **Crystal Structure:** Hexagonal **Density @ 293 K:** 8.9 g/cm3 **Color:** silver

Atomic Structure

 * [[image:http://www.chemicalelements.com/bohr/b0027.gif width="277" height="275"]] ||  || **Number of Energy Levels:** 4
 * First Energy Level:** **Second Energy Level:** **Third Energy Level:** **Fourth Energy Level:** ||

Isotopes

 * ** Isotope ** || ** Half Life ** ||
 * Co-56 || 77.3 days ||
 * Co-57 || 271.8 days ||
 * Co-58 || 70.9 days ||
 * Co-58m || 9.1 hours ||
 * Co-59 || Stable ||
 * Co-60 || 5.3 years ||
 * Co-60m || 10.5 minutes ||
 * Co-61 || 1.7 hours ||

Facts

 * Date of Discovery:** 1737 **Discoverer:** George Brandt **Name Origin:** From the German word //kobalt// or //kobold// (evil spirit) **Uses:** magnets, ceramics, special glasses **Obtained From:** arsenic, oxygen, sulfur, cobaltine

Production
In 2005, the copper deposits in the Katanga Province (former Shaba province) of the Democratic Republic of the Congo were the top producer of cobalt with almost 40% world share, reports the British Geological Survey. The political situation in the Congo influences the price of cobalt significantly. The Mukondo Mountain project, operated by the Central African Mining and Exploration Company in Katanga, may be the richest cobalt reserve in the world. It is estimated to be able to produce about one third of total global production of cobalt in 2008. Several methods exist for the separation of cobalt from copper and nickel. One separation step involves froth flotation, in which surfactants bind to different ore components, leading to an enrichment of cobalt ores. Subsequent roasting converts the ores to the cobalt sulfate, whereas the copper and the iron are oxidized to the oxide. The leaching with water extracts the sulfate together with the arsenates. The residues are further leached with sulfuric acid yielding a solution of copper sulfate. Cobalt can also be leached from the slag of the copper smelter. The products of the above-mentioned processes are transformed into the cobalt oxide (Co 3 O). This oxide is reduced to the metal by the aluminothermic reaction or reduction with carbon in a blast furnace.


 * Chemical Symbol: ||  || Co ||
 * Atomic Number: ||  || 27 ||
 * Atomic Weight: ||  || 58.933 ||
 * Melting Point: ||  || 14944 °C ||
 * Boiling Point: ||  || 2900 °C ||
 * Density of Solid: ||  || 8800 kg m-3 ||
 * Electron Configuration: ||  || 1s2 2s2 2p6 3s2 3p6 3d7 4s2 ||

Abundance

 * [|Amount in average human body (70kg):] ||  || 0.0015 g ||
 * Average amount in Earth's crust: ||  || 25 ppm by mass ||
 * [|Average amount in seawater:] ||  || 0.02 µg L-1 ||


 * Uses of Cobalt**
 * alloyed with iron, nickel and other metals to make Alnico, an alloy of unusual magnetic strength with many important uses (jet engines and gas turbine engines)
 * used in magnet steels and stainless steels
 * used in alloys used in jet turbines and gas turbine generators
 * used in electroplating because of its appearance, hardness, and resistance to oxidation
 * salts are used for the production of brilliant and permanent blue colors in porcelain, glass, pottery, tiles, and enamels
 * cobalt-60, an artificial isotope, is an important γ ray source, and is extensively used as a tracer and a radiotherapeutic agent. Single compact sources of 60Co are readily available
 * compounds are used as paint pigments

Alloys
Cobalt-based superalloys consume most of the produced cobalt. The temperature stability of these alloys makes them suitable for use in turbine blades for gas turbines and jet aircraft engines, though nickel-based single crystal alloys surpass them in this regard. Cobalt-based alloys are also corrosion and wear-resistant. This makes them useful in the medical field, where cobalt is often used (along with titanium) for orthopedic implants that do not wear down over time. The development of the wear-resistant cobalt alloys started in the first decade of the 19th century with the stellite alloys, which are cobalt-chromium alloys with varying tungsten and carbon content. The formation of chromium and tungsten carbides makes them very hard and wear resistant. Special cobalt-chromium-molybdenum alloys like Vitallium are used for prosthetic parts such as hip and knee replacements. Cobalt alloys are also used for dental prosthetics, where they are useful to avoid allergies to nickel. Some high speed steels also use cobalt to increase heat and wear-resistance. The special alloys of aluminium, nickel, cobalt and iron, known as Alnico, and of samarium and cobalt ( samarium-cobalt magnet ) are used in permanent magnets. It is also alloyed with 95% platinum for jewelry purposes, yielding an alloy that is suitable for fine detailed casting and is also slightly magnetic.