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Rhodium
Rhodium is a chemical element with the symbol Rh and atomic number 45. It is a very rare, silvery-white, hard, corrosion-resistant transition metal. It is a noble metal and a member of the platinum group. It has only one naturally occurring isotope: 103Rh. Naturally occurring rhodium is usually found as a free metal or as an alloy with similar metals and rarely as a chemical compound in minerals such as bowieite and rhodplumsite. It is one of the rarest and most valuable precious metals. Rhodium is found in platinum or nickel ores with the other members of the platinum group metals. It was discovered in 1803 by William Hyde Wollaston in one such ore, and named for the rose color of one of its chlorine compounds. The element's major use (consuming about 80% of world rhodium production) is as one of the catalysts in the three-way catalytic converters in automobiles. Because rhodium metal is inert against corrosion and most aggressive chemicals, and because of its rarity, rhodium ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
William Hyde Wollaston
William Hyde Wollaston (; 6 August 1766 – 22 December 1828) was an English chemist and physicist who is famous for discovering the chemical elements palladium and rhodium. He also developed a way to process platinum ore into malleable ingots.Melvyn C. UsselmanWilliam Hyde WollastonEncyclopædia Britannica, retrieved 31 March 2013 Life He was born in East Dereham in Norfolk, the son of the Francis Wollaston (1737–1815), a noted amateur astronomer, and his wife Althea Hyde. He was one of 17 children, but the family was financially well-off and he enjoyed an intellectually stimulating environment. He was educated privately (and remotely) at Charterhouse School from 1774 to 1778 then studied Sciences at Gonville and Caius College, Cambridge. In 1793 he obtained his doctorate (MD) in medicine from Cambridge University, and was a Fellow of his college from 1787 to 1828. He worked as a physician in Huntingdon from 1789 then moved to Bury St Edmunds before moving to London ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Noble Metal
A noble metal is ordinarily regarded as a metallic chemical element that is generally resistant to corrosion and is usually found in nature in its raw form. Gold, platinum, and the other platinum group metals (ruthenium, rhodium, palladium, osmium, iridium) are most often so classified. Silver, copper and mercury are sometimes included as noble metals, however less often as each of these usually occurs in nature combined with sulfur. In more specialized fields of study and applications the number of elements counted as noble metals can be smaller or larger. In physics, there are only three noble metals: copper, silver and gold. In dentistry, silver is not always counted as a noble metal since it is subject to corrosion when present in the mouth. In chemistry, the term noble metal is sometimes applied more broadly to any metallic or semimetallic element that does not react with a weak acid and give off hydrogen gas in the process. This broader set includes copper, mercury, tech ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Precious Metal
Precious metals are rare, naturally occurring metallic chemical elements of high economic value. Chemically, the precious metals tend to be less reactive than most elements (see noble metal). They are usually ductile and have a high lustre. Historically, precious metals were important as currency but are now regarded mainly as investment and industrial raw materials. Gold, silver, platinum, and palladium each have an ISO 4217 currency code. The best known precious metals are the coinage metals, which are gold and silver. Although both have industrial uses, they are better known for their uses in art, jewelry, and coinage. Other precious metals include the platinum group metals: ruthenium, rhodium, palladium, osmium, iridium, and platinum, of which platinum is the most widely traded. The demand for precious metals is driven not only by their practical use but also by their role as investments and a store of value. Historically, precious metals have commanded much higher pri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Symbol (chemistry)
Chemical symbols are the abbreviations used in chemistry for chemical elements, functional groups and chemical compounds. Element symbols for chemical elements normally consist of one or two letters from the Latin alphabet and are written with the first letter capitalised. History Earlier symbols for chemical elements stem from classical Latin and Greek vocabulary. For some elements, this is because the material was known in ancient times, while for others, the name is a more recent invention. For example, Pb is the symbol for lead (''plumbum'' in Latin); Hg is the symbol for mercury (''hydrargyrum'' in Greek); and He is the symbol for helium (a new Latin name) because helium was not known in ancient Roman times. Some symbols come from other sources, like W for tungsten (''Wolfram'' in German) which was not known in Roman times. A three-letter temporary symbol may be assigned to a newly synthesized (or not yet synthesized) element. For example, "Uno" was the temporary symbol fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palladium
Palladium is a chemical element with the symbol Pd and atomic number 46. It is a rare and lustrous silvery-white metal discovered in 1803 by the English chemist William Hyde Wollaston. He named it after the asteroid Pallas, which was itself named after the epithet of the Greek goddess Athena, acquired by her when she slew Pallas. Palladium, platinum, rhodium, ruthenium, iridium and osmium form a group of elements referred to as the platinum group metals (PGMs). They have similar chemical properties, but palladium has the lowest melting point and is the least dense of them. More than half the supply of palladium and its congener platinum is used in catalytic converters, which convert as much as 90% of the harmful gases in automobile exhaust (hydrocarbons, carbon monoxide, and nitrogen dioxide) into nontoxic substances (nitrogen, carbon dioxide and water vapor). Palladium is also used in electronics, dentistry, medicine, hydrogen purification, chemical applications, groundwate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Platinum Group
The platinum-group metals (abbreviated as the PGMs; alternatively, the platinoids, platinides, platidises, platinum group, platinum metals, platinum family or platinum-group elements (PGEs)) are six noble, precious metallic elements clustered together in the periodic table. These elements are all transition metals in the d-block (groups 8, 9, and 10, periods 5 and 6). The six platinum-group metals are ruthenium, rhodium, palladium, osmium, iridium, and platinum. They have similar physical and chemical properties, and tend to occur together in the same mineral deposits. However, they can be further subdivided into the iridium-group platinum-group elements (IPGEs: Os, Ir, Ru) and the palladium-group platinum-group elements (PPGEs: Rh, Pt, Pd) based on their behaviour in geological systems. The three elements above the platinum group in the periodic table (iron, nickel and cobalt) are all ferromagnetic; these, including the lanthanide element gadolinium, are the only known tr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Discovery Of The Chemical Elements
The discovery of the 118 chemical elements known to exist as of 2022 is presented in chronological order. The elements are listed generally in the order in which each was first defined as the pure element, as the exact date of discovery of most elements cannot be accurately determined. There are plans to synthesize more elements, and it is not known how many elements are possible. Each element's name, atomic number, year of first report, name of the discoverer, and notes related to the discovery are listed. Periodic table of elements Ancient discoveries Modern discoveries Graphics See also * History of the periodic table * Periodic table * Extended periodic table * ''The Mystery of Matter: Search for the Elements'' (2014/2015 PBS film) * Transfermium Wars References External linksHistory of the Origin of the Chemical Elements and Their DiscoverersLast updated by Boris Pritychenko on March 30, 2004 [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catalytic Converter
A catalytic converter is an exhaust emission control device that converts toxic gases and pollutants in exhaust gas from an internal combustion engine into less-toxic pollutants by catalyzing a redox reaction. Catalytic converters are usually used with internal combustion engines fueled by gasoline or diesel, including lean-burn engines, and sometimes on kerosene heaters and stoves. The first widespread introduction of catalytic converters was in the United States automobile market. To comply with the U.S. Environmental Protection Agency's stricter regulation of exhaust emissions, most gasoline-powered vehicles starting with the 1975 model year are equipped with catalytic converters. These "two-way" converters combine oxygen with carbon monoxide (CO) and unburned hydrocarbons (HC) to produce carbon dioxide (CO2) and water (H2O). Although two-way converters on gasoline engines were rendered obsolete in 1981 by "three-way" converters that also reduce oxides of nitrogen (); they ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Colored Gold
Pure gold is slightly reddish yellow in color, but colored gold in various other colors can be produced by alloying gold with other elements. Colored golds can be classified in three groups: * Alloys with silver and copper in various proportions, producing white, yellow, green and red golds. These are typically malleable alloys. * Intermetallic compounds, producing blue and purple golds, as well as other colors. These are typically brittle, but can be used as gems and inlays. * Surface treatments, such as oxide layers. Pure 100% (in practice, 99.9% or better) gold is 24 karat by definition, so all colored golds are less pure than this, commonly 18K (75%), 14K (58.5%), 10K (41.6%), or 9K (37.5%). Alloys White gold White gold is an alloy of gold and at least one white metal (usually nickel, silver, or palladium). Like yellow gold, the purity of white gold is given in karats. White gold's properties vary depending on the metals used and their proportions. As a result, white gold ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transition Metal
In chemistry, a transition metal (or transition element) is a chemical element in the d-block of the periodic table (groups 3 to 12), though the elements of group 12 (and less often group 3) are sometimes excluded. They are the elements that can use d orbitals as valence orbitals to form chemical bonds. The lanthanide and actinide elements (the f-block) are called inner transition metals and are sometimes considered to be transition metals as well. Since they are metals, they are lustrous and have good electrical and thermal conductivity. Most (with the exception of group 11 and group 12) are hard and strong, and have high melting and boiling temperatures. They form compounds in any of two or more different oxidation states and bind to a variety of ligands to form coordination complexes that are often coloured. They form many useful alloys and are often employed as catalysts in elemental form or in compounds such as coordination complexes and oxides. Most are strongly param ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bowieite
Bowieite is a rhodium-iridium-platinum sulfide mineral (Rh,Ir,Pt)2S3, found in platinum-alloy nuggets from Goodnews Bay, Alaska. It was named (by the IMA in 1984) after the British scientist Stanley Bowie (1917–2008), in recognition of his work on identification of opaque minerals. The mineral crystallizes in the orthorhombic crystal system In crystallography, the orthorhombic crystal system is one of the 7 crystal systems. Orthorhombic lattices result from stretching a cubic lattice along two of its orthogonal pairs by two different factors, resulting in a rectangular prism with ... (space group ''Pbcn''). References New mineral 1984 {{Sulfide-mineral-stub Iridium minerals Platinum minerals Rhodium minerals Sulfide minerals Orthorhombic minerals Minerals in space group 60 Minerals described in 1984 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhodplumsite
Rhodplumsite is a rare rhodium-lead sulfide mineral, chemical formula Rh3Pb2S2. It was originally discovered within a platinum nugget, in grains up to 40 μm in size. Its name originates from its composition; rhodium and lead (plumbum in Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...). Although this mineral contains large amounts of rhodium, it is not an economically viable ore of rhodium due to its rarity. References Rhodium minerals Lead minerals Sulfide minerals Trigonal minerals Minerals in space group 166 Minerals described in 1983 {{Sulfide-mineral-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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