platinum
platinum
Symbol: Pt
Atomic number: 78
Atomic weight: 195.078
Attractive greyish-white metal. When pure, it is malleable and ductile. Does not oxidize in air, insoluble in hydrochloric and nitric acid. Corroded by halogens, cyandies, sulphur and alkalis. Hydrogen and oxygen react explosively in the presence of platinum. There are six stable isotopes and three radioisotopes, the most stable being Pt-193 with a half-life of 60 years. Platinum is used in jewelry, laboratory equipment, electrical contacts, dentistry, and anti-pollution devices in cars. PtCl2(NH3)2 is used to treat some forms of cancer. Platinum-cobalt alloys have magnetic properties. It is also used in the definition of the Standard Hydrogen Electrode. Discovered by Antonio de Ulloa in South America in 1735. The name comes from the Spanish word platina which means silver. Platinum metal is generally not a health concern due to its unreactivity, however platinum compounds should be considered highly toxic.

Elements of periodic system. 2013.

  • Platinum — Студийный альбом Майк Олдфилд …   Википедия

  • Platinum — Plat i*num, n. [NL., fr. Sp. platina, from plata silver, LL. plata a thin plate of metal. See {Plate}, and cf. {Platina}.] (Chem.) A metallic element of atomic number 78, one of the noble metals, classed with silver and gold as a precious metal,… …   The Collaborative International Dictionary of English

  • platinum — plat‧i‧num [ˈplætnəm] noun [uncountable] a silver grey metal used in manufacturing and traded on commodity market S: • a platinum mine • platinum jewellery * * * platinum UK US /ˈplætɪnəm/ US  /ˈplætənəm/ noun [U] …   Financial and business terms

  • Platinum — Platinum, AK U.S. city in Alaska Population (2000): 41 Housing Units (2000): 26 Land area (2000): 44.630629 sq. miles (115.592794 sq. km) Water area (2000): 0.071778 sq. miles (0.185904 sq. km) Total area (2000): 44.702407 sq. miles (115.778698… …   StarDict's U.S. Gazetteer Places

  • platinum — ☆ platinum [plat′ n əm] n. [ModL < Sp platina, dim. of plata, silver < Prov, metal plate, silver bar, silver < VL * plattus, flat: see PLATE] a silver colored, malleable, ductile, metallic chemical element that is highly resistant to… …   English World dictionary

  • platinum — metallic element, Modern Latin, from Sp. platina platinum, dim. of plata silver, from O.Fr. plate or O.Prov. plata sheet of metal (see PLATE (Cf. plate)). The metal looks like silver, and the Spaniards at first thought it an inferior sort of… …   Etymology dictionary

  • platinum — ► NOUN 1) a precious silvery white metallic chemical element used in jewellery and in some electrical and laboratory apparatus. 2) (before another noun ) greyish white or silvery like platinum. ORIGIN Spanish platina, from plata silver …   English terms dictionary

  • Platinum — This article is about the chemical element. For other uses, see Platinum (disambiguation). iridium ← platinum → gold Pd ↑ Pt ↓ Ds …   Wikipedia

  • platinum — /plat n euhm, plat neuhm/, n. 1. Chem. a heavy, grayish white, highly malleable and ductile metallic element, resistant to most chemicals, practically unoxidizable except in the presence of bases, and fusible only at extremely high temperatures:… …   Universalium

  • Platinum — Cette page d’homonymie répertorie les différents sujets et articles partageant un même nom. Sur les autres projets Wikimedia : « Platinum », sur le Wiktionnaire (dictionnaire universel) Platinum est le mot anglais désignant le… …   Wikipédia en Français