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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 ...
This metal would later be identified as a new chemical element, now known as platinum. [2] Ulloa is therefore often credited as the discoverer of platinum. [3] [4] Map by Jorge Juan and Antonio de Ulloa of the triangulation carried out between Quito and Cuenca by the French Geodesic Mission to the Equator, in 1735–1744.
In 1840, Claus, received a substantial amount of platinum ore samples for his studies from the Ural Mountains and the St Petersburg Mint and started working on chemistry and isolation of noble metals, in particular rhodium, iridium, osmium, and to a lesser extent, palladium and platinum. In 1844, he discovered a new chemical element, which he ...
Perey discovered it as a decay product of 227 Ac. [177] 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]
The other metals discovered before the Scientific Revolution largely fit the pattern, except for high-melting platinum: Bismuth melts at 272 °C (521 °F) [21] Zinc melts at 420 °C (787 °F), [21] but importantly boils at 907 °C (1665 °F), a temperature below the melting point of silver. Consequently, at the temperatures needed to reduce ...
Chemical analysis related to the process of purifying platinum led Wollaston to discover the elements palladium (symbol Pd) in 1802 and rhodium (symbol Rh) in 1804. [1] When Anders Gustav Ekeberg discovered tantalum in 1802 Wollaston declared the new element identical with niobium (then known as columbium).
Humphry Davy had discovered a few years earlier that a hot platinum wire lit up in a mixture of coal gas and air. [10]) This release of energy from oxidation of the compounds, without flame, and without change in the platinum itself, was a sign of the catalytic property of platinum investigated later by Johann Döbereiner and other chemists.
The earliest known powder metallurgy, and earliest working of platinum in the world, was apparently developed by the cultures of Esmeraldas (northwest Ecuador) before the Spanish conquest [17] Beginning with the La Tolita culture (600 BC – 200 CE), Ecuadorian cultures mastered the soldering of platinum grains through alloying with copper ...