'Ellson+Chow'+Platinum+-+Beautiful+Metal

PLATINUM. Symbol: Pt Atomic number: 78 Standard atomic weight: [|195.084] [|g·mol−1] Electric configuration: 2.8.18.32.17.1 [ [|Xe]  ] 4f14 5d9 6s1 Melting point: 1768.3 ° [|C] Boiling point: 3825 ° [|C] Density: 21.4 5 [|g·cm−3]

Platinum is a beautiful silvery-white metal, when pure, and is malleable, ductile and dense. The metal does not oxidise in air at any temperature, but is corroded by halogens, cyanides, sulphur and caustic alkalis. Platinum occurs natively, accompanied by small quantities of [|iridium], [|osmium] , [|palladium] , [|ruthenium] , and [|rhodium] , all belonging to the same group of metals. The most common [|oxidation states] of platinum are +2 and +4. Platinum compounds often come in the form of fluorides, chlorides, iodides, bromides, and others like oxides and sulphides.

Produced from platinum ore or native platinum deposits. Primary mining areas are Urals in Russia, Canada, South Africa Columbia and Peru. Annual world wide production is around 30 tons. It occurs mostly in South Africa, which accounts for 80% of the world production.
 * Sources of Platinum:**

**Uses** Of the 239 tonnes of platinum sold in 2006, 130 tonnes were used for [|vehicle emissions control] devices, 49 tonnes for jewellery, 13.3 tonnes in electronics, and 11.2 tonnes in the chemical industry as a catalyst. The remaining 35.5 tonnes went to various other minor applications, such as electrodes, anticancer drugs, oxygen sensors, spark plugs and turbine engines.

Platinum is used in [|catalytic converters], laboratory equipment, [|electrical] contacts and [|electrodes] , [|platinum resistance thermometers] , [|dentistry] equipment, and jewelry. Because only a few hundred tonnes are produced annually, it is a scarce material, and is highly valuable and is a major [|precious metal commodity]. Being a [|heavy metal], it leads to health issues upon exposure to its salts, but due to its corrosion resistance it is not toxic as a metal. Some of its compounds, most notably [|cisplatin], are applied in [|chemotherapy] against certain types of cancer. .

Platinum finds use in jewellery and also watches, usually as a 90–95% alloy, due to its inertness and shine. Watchmakers appreciate the unique properties of platinum, as it neither tarnishes nor wears out (relative to gold). In the laboratory, platinum wire is used for electrodes; platinum pans and supports are used in [|thermo gravimetric analysis] because of the stringent requirements of chemical inertness upon heating to high temperatures (~1000°C). Platinum is used as an alloying agent for various metal products, including fine wires, noncorrosive laboratory containers, medical instruments, dental prostheses, electrical contacts, and thermocouples. Platinum-cobalt, an alloy of roughly three parts platinum and one part cobalt, is used to make relatively strong permanent [|magnets]. Platinum-based anodes are used in ships, pipelines, and steel piers. Platinum is widely used as a [|catalyst]. It will convert methyl alcohol vapours (CH4O) into formaldehyde (CH2O) on contact, glowing red hot in the process. This effect is used to make small hand warmers. Platinum is also used in a device called a catalytic converter, a device found in the exhaust systems of most cars. Catalytic converters combine carbon monoxide (CO) and unburned fuel from a car's exhaust with [|oxygen] from the air, forming carbon dioxide (CO2) and water vapour (H2O). Platinum is also used as a catalyst in the production of sulphuric acid (H2SO4) and in the cracking of petroleum products. Fuel cells, devices that combine [|hydrogen] and oxygen to produce electricity and water, also use platinum as a catalyst.

Reactions of Platinum

Platinum does not normally react with air or water.

Careful control of the reaction between platinum metal and fluorine gas gives either the volatile platinum(VI) fluoride, PtF6 or the tetrameric platinum(V) fluoride, (PtF5)4. The latter product disproportionates into platinum(VI) fluoride and platinum(IV) fluoride, PtF4.
 * Reaction of platinum with the halogens **


 * Pt(s) + 3F2(g) > **** PtF6(s) [dark red] **
 * 4Pt(s) + 10F2(g) > **** (PtF5)4(s) [deep red] **
 * (PtF5)4(s)> **** PtF6(s) + PtF4(s) [yellow brown] **

PtCl4, PtBr4 and PtI4 are formed in the reactions of platinum metal and chlorine, Cl2, bromine, Br2, or iodine, I2.


 * Pt(s) + 2Cl2(g)> **** PtCl4(s) [red brown] **
 * Pt(s) + 2Br2(g)> **** PtBr4(s) [brown black] **
 * Pt(s) + 2I2(g)> **** PtI4(s) [brown black] **

PtCl2 is also formed in the controlled reaction of platinum metal and chlorine. Depending upon the reaction conditio9ns, one of two different forms of PtCl2 is formed.
 * Pt(s) + Cl2(g)> **** PtCl2(s) [dark red or olive green] **

Sources: en.wikipedia.org/wiki/**Platinum** education.jlab.org/itselemental/ele078.html periodic.lanl.gov/elements/78.html www.mindat.org/min-3236.html www.chemicalelements.com/elements/pt.html environmentalchemistry.com/yogi/periodic/Pt.html