![]() It is the only stable isotope with a non-zero spin. Platinum has six naturally occurring isotopes: 190 In 2007, the German scientist Gerhard Ertl won the Nobel Prize in Chemistry for determining the detailed molecular mechanisms of the catalytic oxidation of carbon monoxide over platinum ( catalytic converter). Numerous DMSO complexes have been reported and care is taken in the choosing of reaction solvents. Platinum is insoluble in hydrochloric and nitric acid, but dissolves in hot aqua regia (a mixture of nitric and hydrochloric acids), to form aqueous chloroplatinic acid, H 2PtCl 6: Pt + 4 HNO 3 + 6 HCl → H 2PtCl 6 + 4 NO 2 + 4 H 2OĪs a soft acid, the Pt 2+ ion has a great affinity for sulfide and sulfur ligands. It reacts vigorously with fluorine at 500 ☌ (932 ☏) to form platinum tetrafluoride. Although elemental platinum is generally unreactive, it is attacked by chlorine, bromine, iodine, and sulfur. Tetracoordinate platinum(II) compounds tend to adopt 16-electron square planar geometries. The +1 and +3 oxidation states are less common, and are often stabilized by metal bonding in bimetallic (or polymetallic) species. The most common oxidation states of platinum are +2 and +4. Bulk platinum does not oxidize in air at any temperature, but it forms a thin surface film of PtO 2 that can be easily removed by heating to about 400 ☌. ![]() Platinum has excellent resistance to corrosion. See also: Platinum group Platinum being dissolved in hot aqua regia Its resistance to wear and tarnish is well suited to use in fine jewellery. Its physical characteristics and chemical stability make it useful for industrial applications. ![]() Platinum is more ductile than gold, silver or copper, thus being the most ductile of pure metals, but it is less malleable than gold. Pure platinum is a lustrous, ductile, and malleable, silver-white metal. In early 2021, the value of platinum ranged from US$1,055 to US$1,320 per troy ounce. Pure platinum is currently less expensive than pure gold, having been so continuously since 2015, but has been twice as expensive or more, mostly prior to 2008. Compounds containing platinum, such as cisplatin, oxaliplatin and carboplatin, are applied in chemotherapy against certain types of cancer. As a heavy metal, it leads to health problems upon exposure to its salts but due to its corrosion resistance, metallic platinum has not been linked to adverse health effects. Platinum is used in the glass industry to manipulate molten glass which does not " wet" platinum. Platinum is used in catalytic converters, laboratory equipment, electrical contacts and electrodes, platinum resistance thermometers, dentistry equipment, and jewelry. It was referenced in European writings as early as the 16th century, but it was not until Antonio de Ulloa published a report on a new metal of Colombian origin in 1748 that it began to be investigated by scientists. Because it occurs naturally in the alluvial sands of various rivers, it was first used by pre-Columbian South American natives to produce artifacts. Consequently, platinum is often found chemically uncombined as native platinum. It has remarkable resistance to corrosion, even at high temperatures, and is therefore considered a noble metal. Platinum is one of the least reactive metals. Because of its scarcity in Earth's crust, only a few hundred tonnes are produced annually, and given its important uses, it is highly valuable and is a major precious metal commodity. It occurs in some nickel and copper ores along with some native deposits, mostly in South Africa, which accounts for ~80% of the world production. It is one of the rarer elements in Earth's crust, with an average abundance of approximately 5 μg/kg. Platinum is a member of the platinum group of elements and group 10 of the periodic table of elements. Its name originates from Spanish platina, a diminutive of plata "silver". It is a dense, malleable, ductile, highly unreactive, precious, silverish-white transition metal. Platinum is a chemical element it has symbol Pt and atomic number 78.
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