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Platinum is a chemical element; it has symbol Pt and atomic number 78. It is a dense, malleable, ductile, highly unreactive, precious, silverish-white transition metal. Its name originates from Spanish platina, a diminutive of plata "silver". [7] [8] Platinum is a member of the platinum group of elements and group 10 of the periodic table of ...
Only gold, silver, copper and the platinum group occur native in large amounts. [citation needed] Over geological time scales, very few metals can resist natural weathering processes like oxidation, so mainly the less reactive metals such as gold and platinum are found as native metals. The others usually occur as isolated pockets where a ...
The platinum-group metals (PGMs), also known as 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 ...
A noble metal is ordinarily regarded as a metallic 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.
Naturally occurring platinum (78 Pt) consists of five stable isotopes (192 Pt, 194 Pt, 195 Pt, 196 Pt, 198 Pt) and one very long-lived (half-life 4.83×10 11 years) radioisotope (190 Pt). There are also 34 known synthetic radioisotopes, the longest-lived of which is 193 Pt with a half-life of 50 years. All other isotopes have half-lives under a ...
Francium was the last element to be discovered in nature, rather than synthesized in the lab, although four of the "synthetic" elements that were discovered later (plutonium, neptunium, astatine, and promethium) were eventually found in trace amounts in nature as well. [178]
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The chemical elements can be broadly divided into metals, metalloids, and nonmetals according to their shared physical and chemical properties.All elemental metals have a shiny appearance (at least when freshly polished); are good conductors of heat and electricity; form alloys with other metallic elements; and have at least one basic oxide.