Cobalt! please help im not finding anything?

Sean

2007-04-09 17:41:40 UTC

WIKIPEDIA INFORMATION IS WRONG!!!!!! here is my entire Cobalt i wrote for science this year (its alot of info but it kicks ***), [it got me a 96!!!!] All this information is legit and true i spent a month researching and writing about it. this is all the information you will ever need on Cobalt. NONE OF THIS IS PLAGERIZED AND IT IS ALL PUT IN MY OWN WORDS!!!

Cobalt is a vital element. It is one of the 27 elements that are imperative to man. This element is used to make the color Cobalt Blue as a representation of dark blue ink or paint found in an art class. Research on Cobalt revels that this element is a transition metal that when mixed with sulfate will present as a dark blue color. Also interesting is a fact that Cobalt is a very important element which interfaces with all aspects of mans’ fundamental life being.

The word Cobalt comes from the German word “Kobald” which means goblin or evil sprit. “Kobold” came from the myth that this metal contaminated other mined elements. Cobalt is also derived from the Greek term “Cobalos” which means “mine.” Cobalt was discovered by Georg Brandt a Swedish chemist in 1735. He was trying to prove that Cobalt was different than Bismuth. The atomic structure of cobalt is 27 protons 32 neutrons and 27 electrons. Cobalt is a brittle, hard metal with a crystalline atomic structure. Here are two representations of Cobalt’s electron shell.

Cobalt is a fundamental element as it is a component of the B12 vitamin which is necessary for all life. Vitamin B12 is a part of the vitamin B complex and it promotes the production of red blood cells, nerve cells and the production of DNA in mammals. It is naturally found in meat, eggs, fish, poultry and milk products. Lack of B12 in humans can result in anemia, cardiovascular disease, coronary heart disease and strokes. Vegans are at risk for these diseases since their diet may not include sufficient B12. A vegan is a vegetarian who eats plant products only, especially one who uses no products derived from animals, as fur or leather. Some vegetarian foods such as “Marmite” a popular food-spread in the United Kingdom has Cobalt in it as a source of vitamin B12. Australia has a similar spread called “Vegemite” that also contains Cobalt as a source of vitamin B12.

Cobalt 60, a radioactive isotope, is a man-made atom that is used in a wide range of medical applications. Two such applications are sterilizing medical equipment and radiation treatment. An isotope is one of two or more atoms containing the identical atomic number but unlike mass numbers. Cobalt 60 can be utilized into a doomsday device called a Cobalt Bomb. Such a bomb emits intense gamma rays which highly deadly. Theoretically, this device could eradicate all life on earth. Interesting is the fact that Cobalt 60 is unstable and loses 50 percent of its radioactivity every 5.27 years eventually becoming stable decaying into nickel-60.

Cobalt is one of the three transition metals that are known to create a magnetic field. When Cobalt is combined with nickel and aluminum it forms an alloy called Alnico which is used to make permanent magnets that are powerful. It is because of Cobalt’s magnet properties which make it the key ingredient to for the surface coating on audio and video recording tape. The magnetic charges orchestrated by the recording head uniquely arrange the magnetic charges on the tape to preserve the audio-visual for replay at a later time. This same principal is used in the plastic credit card type hotel door keys which allow entry into the hotel room.

Cobalt is also used to form alloys that are used in a variety of engines such as gas turbines and jet engines. It has also been alloyed with chromium and tungsten to make heavy duty cutting tools that can sustain high speeds and temperatures. Even as Cobalt increases in temperature toward its melting point of 1493 degrees Celsius or 2719.4 degrees Fahrenheit this metal does not loose its hardness. It is because of this characteristic Cobalt is used in high speed cutting tools frequently used to machine tough exotic metals such as titanium into aerospace parts.

Cobalt is a hard metal which has a naturally smooth appearance. It’s because of this and its magnetic properties Cobalt is used in electroplating to prevent oxidation of other metals. Electroplating is a finishing process by which a part is submerged in an electrically charged Cobalt bath solution, where plating material is attracted to metal surfaces to produce a finish-coat or for rust protection.

Just like in grade school art projects, salts from cobalt have been used to give a number of objects such as porcelain, glass and pottery, a bright blue color. This same salt is used by farmers for animal nutrition in the form of cobalt salt licks. This helps the animals to grow strong and prevent disease.

Although Cobalt is found in meteorites and is present in manganese nodules that develop through heat vents at the bottom of the ocean, this is not where it is mined. Although the manganese nodules are a substantial source of Cobalt, there is no practical method of harvesting the nodules. Typically Cobalt is collected by excavating and processing silver, nickel, iron, copper, and lead. Most of the world’s Cobalt is harvested mainly in: Australia, Canada, Congo, Russia, and Zambia. The United States has very low cobalt production, most of it coming from mines in Minnesota. Canada is the largest producer of Cobalt which is mined mostly in central Canada by a Nickel mining company called INCO.

Through its wide and diverse use and applications Cobalt is an essential element contributing to medical, agricultural and industrial industries through which man has greatly benefited. Cobalt is not a metal which is readily recognized by the average person but it closely interfaces with each of us providing health and technological enhancements which are taken for granted. Living conditions as we know them would be very different and towards the negative without the natural or deliberate introduction of Cobalt to life and metallurgical science.

2016-03-18 02:36:51 UTC

Jennifer, Thank you for your interest in our vehicles. I would advise you to look at GM Certified on the web to find a used Cobalt in your price range. Thank you Elizabeth, GM Customer Service

bakfanlin

2007-04-09 17:35:55 UTC

Try this site. It has a lot of information on Cobalt....

utpostman

2007-04-09 17:57:56 UTC

http://en.wikipedia.org/wiki/Cobalt

Sarah W

2007-04-09 17:35:05 UTC

http://en.wikipedia.org/wiki/Cobalt

follow that link, youll get all the info you will need, and its from a good source

2007-04-09 17:35:10 UTC

Goto www.wikipedia.org

Mary O

2007-04-09 17:37:53 UTC

Your continued donations keep Wikipedia running!

Cobalt

From Wikipedia, the free encyclopedia

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For other uses, see Cobalt (disambiguation).

27 iron ← cobalt → nickel

-

↑

Co

↓

Rh

Periodic Table - Extended Periodic Table

General

Name, Symbol, Number cobalt, Co, 27

Chemical series transition metals

Group, Period, Block 9, 4, d

Appearance metallic with gray tinge

Standard atomic weight 58.933195(5) g·mol−1

Electron configuration [Ar] 4s2 3d7

Electrons per shell 2, 8, 15, 2

Physical properties

Density (near r.t.) 8.90 g·cm−3

Liquid density at m.p. 7.75 g·cm−3

Melting point 1768 K

(1495 °C, 2723 °F)

Boiling point 3200 K

(2927 °C, 5301 °F)

Heat of fusion 16.06 kJ·mol−1

Heat of vaporization 377 kJ·mol−1

Heat capacity (25 °C) 24.81 J·mol−1·K−1

Vapor pressure P(Pa) 1 10 100 1 k 10 k 100 k

at T(K) 1790 1960 2165 2423 2755 3198

Atomic properties

Crystal structure hexagonal

Oxidation states 2, 3

(amphoteric oxide)

Electronegativity 1.88 (Pauling scale)

Ionization energies

(more) 1st: 760.4 kJ·mol−1

2nd: 1648 kJ·mol−1

3rd: 3232 kJ·mol−1

Atomic radius 135 pm

Atomic radius (calc.) 152 pm

Covalent radius 126 pm

Miscellaneous–

Magnetic ordering ferromagnetic

Electrical resistivity (20 °C) 62.4 n Ω·m

Thermal conductivity (300 K) 100 W·m−1·K−1

Thermal expansion (25 °C) 13.0 µm·m−1·K−1

Speed of sound (thin rod) (20 °C) 4720 m/s

Young's modulus 209 GPa

Shear modulus 75 GPa

Bulk modulus 180 GPa

Poisson ratio 0.31

Mohs hardness 5.0

Vickers hardness 1043 MPa

Brinell hardness 700 MPa

CAS registry number 7440-48-4

Selected isotopes

Main article: Isotopes of cobalt iso NA half-life DM DE (MeV) DP

56Co syn 77.27 d ε 4.566 56Fe

57Co syn 271.79 d ε 0.836 57Fe

58Co syn 70.86 d ε 2.307 58Fe

59Co 100% Co is stable with 32 neutrons

60Co syn 5.2714 years β- 2.824 60Ni

References

Cobalt (IPA: /ˈkəʊbɒlt/) is a hard, lustrous, silver-gray metal, a chemical element with symbol Co. It is found in various ores, and is used in the preparation of magnetic, wear-resistant, and high-strength alloys. Its compounds are used in the production of inks, paints, and varnishes.

Contents [hide]

1 Notable characteristics

2 Applications

2.1 Use in medicine

3 History

4 Biological role

5 Occurrence

6 Compounds

7 Isotopes

8 Precautions

9 References

10 Notes

11 External links

[edit] Notable characteristics

Cobalt is a silver or grey ferromagnetic with atomic number 27. The Curie temperature is of 1388 K with 1.6~1.7 Bohr magnetons per atom. It is frequently associated with nickel, and both are characteristic ingredients of meteoric iron. Mammals require small amounts of cobalt salts. Cobalt-60, an artificially produced radioactive isotope of cobalt, is an important radioactive tracer and cancer-treatment agent. Cobalt has a relative permeability two thirds that of iron. Metallic cobalt commonly presents a mixture of two crystallographic structures hcp and fcc with a transition temperature hcp→fcc of 722 K.

Common oxidation states of cobalt include +2 and +3, though +1 is also seen.

[edit] Applications

Alloys, such as:

Superalloys, for parts in gas turbine aircraft engines.

Corrosion- and wear-resistant alloys.

High speed steels.

Cemented carbides (also called hard metals) and diamond tools.

Magnets and magnetic recording media.

Alnico magnets.

Samarium-cobalt magnets.

Catalysts for the petroleum and chemical industries.

Electroplating because of its appearance, hardness, and resistance to oxidation.

Drying agents for paints, varnishes, and inks.

Ground coats for porcelain enamels.

Pigments (cobalt blue and cobalt green).

Cobalt blue glass

Lithium ion battery electrodes.

Steel-belted radial tires.

Cobalt-60 has multiple uses as a gamma ray source:

It is used in radiotherapy.

It is used in radiation treatment of foods for sterilization (cold pasteurization).

It is used in industrial radiography to detect structural flaws in metal parts.

Co-60 is useful as a gamma ray source partially because it can be produced - in known quantity, and very large amounts - by simply exposing natural cobalt to neutrons in a reactor for a given time.

[edit] Use in medicine

Cobalt-60 (Co-60 or 60Co) is a radioactive metal that is used in radiotherapy. It produces two gamma rays with energies of 1.17 MeV and 1.33 MeV. The 60Co source is about 2 cm in diameter and as a result produces a geometric penumbra, making the edge of the radiation field fuzzy. The metal has the unfortunate habit of producing a fine dust, causing problems with radiation protection. The 60Co source is useful for about 5 years but even after this point is still very radioactive, and so cobalt machines have fallen from favor in the Western world where linacs are common. Cobalt with alloying additions of chromium and molybdenum is widely used as a bio-medical implant material.

[edit] History

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 AD 79), and in China dating from the Tang dynasty (AD 618–907) and the Ming dynasty (AD 1368–1644)[1]. Cobalt glass ingots have been recovered from shipwrecks dating to the time of the Minoans[citation needed].

Swedish chemist Georg Brandt (1694–1768) is credited with isolating cobalt sometime between 1730 and 1737. He was able to show that cobalt was the source of the blue color in glass, which previously had been attributed to the bismuth found with cobalt.

During the 19th century, cobalt blue was produced at the Norwegian Blaafarveværket (70-80 % of world production), led by the Prussian industrialist Benjamin Wegner.

In 1938, John Livingood and Glenn Seaborg discovered cobalt-60.

The word cobalt is derived from the German kobalt, from kobold meaning "goblin", a term used for the ore of cobalt by miners, who thought it worthless and who found that it was poisonous and that it polluted and degraded other mined elements, mainly due to the arsenic and sulfur also found in the ore[2].

[edit] Biological role

Cobalt in small amounts is essential to many living organisms, including humans. Having 0.13 to 0.30 mg/kg of cobalt in soils markedly improves the health of grazing animals. Cobalt is a central component of the vitamin cobalamin, or vitamin B-12.

[edit] Occurrence

Cobalt oreCobalt is not found as a free metal and is generally found in the form of ores. Cobalt is usually not mined alone, and tends to be produced as a by-product of nickel and copper mining activities. The main ores of cobalt are cobaltite, erythrite, glaucodot, and skutterudite. The world's major producers of cobalt are the Democratic Republic of the Congo, the People's Republic of China, Zambia, Russia and Australia. It is also found in Finland, Azerbaijan, Kazakhstan and Morocco. It is also produced in the mines of Cobalt, Ontario as a byproduct of silver mining.

see also Category:Cobalt minerals

[edit] Compounds

There is a wide variety of cobalt compounds. The +2 and +3 oxidation states are most prevalent, however cobalt(I) complexes are also fairly common. Cobalt(II) salts form the red-pink [Co(OH2)6]2+ complex in aqueous solution. Adding excess chloride will also change the colour from pink to blue, due to the formation of [CoCl4]2-. Cobalt oxides are antiferromagnetic at low temperature: CoO (Neel temperature 291 K) and Co3O4 (Neel temperature: 40 K).

see also Category:Cobalt compounds

[edit] Isotopes

Naturally occurring cobalt is composed of 1 stable isotope, 59Co. 22 radioisotopes have been characterized with the most stable being 60Co with a half-life of 5.2714 years, 57Co with a half-life of 271.79 days, 56Co with a half-life of 77.27 days, and 58Co with a half-life of 70.86 days. All of the remaining radioactive isotopes have half-lives that are less than 18 hours and the majority of these have half-lives that are less than 1 second. This element also has 4 meta states, all of which have half-lives less than 15 minutes.

The isotopes of cobalt range in atomic weight from 50 u (50Co) to 73 u (73Co). The primary decay mode before the most abundant stable isotope, 59Co, is electron capture and the primary mode after is beta decay. The primary decay products before 59Co are element 26 (iron) isotopes and the primary products after are element 28 (nickel) isotopes.

[edit] Precautions

Powdered cobalt in metal form is a fire hazard. Cobalt compounds should be handled with care due to cobalt's slight toxicity.

60Co is a powerful gamma ray emitter and exposure to it is therefore a cancer risk. Ingestion of 60Co will lead to incorporation of some cobalt into tissues, which is released very slowly. 60Co is a risk factor in a nuclear confrontation because neutron emissions will convert 59Co into this isotope. Some nuclear weapon designs could intentionally increase the amount of 60Co dispersed as nuclear fallout – this is sometimes called a dirty bomb or cobalt bomb, once predicted by a leading scientist as being capable of wiping out all life on earth.[citation needed] The risk in the absence of a nuclear war comes from improper handling (or theft) of medical radiotherapeutic units. Nevertheless, the gamma radiation emitted from 60Co is used to kill bacteria on fruit and vegetables thus increasing their shelf life. This process is referred to as irradiation.

[edit] References

Los Alamos National Laboratory - Cobalt

[edit] Notes

^ Encyclopedia Britannica Online.

^ Oxford English Dictionary, Second Edition. 1989.

[edit] External links

Wikimedia Commons has media related to:

CobaltLook up cobalt in

Wiktionary, the free dictionary.National Pollutant Inventory - Cobalt fact sheet

WebElements.com – Cobalt

London celebrates 50 years of Cobalt-60 Radiotherapy

Links to external chemical sources

Retrieved from "http://en.wikipedia.org/wiki/Cobalt"