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osmiumenUK
os·mi·um O0138100 (ŏz′mē-əm)n. Symbol Os A bluish-white, hard, brittle and extremely dense metallic element, found in small amounts in osmiridium, nickel, and platinum ores. It is used as a platinum hardener and in making pen points, phonograph needles, instrument pivots, and other wear-resistant items. Atomic number 76; atomic weight 190.2; melting point 3,033°C; boiling point 5,012°C; specific gravity 22.587; valence 2, 3, 4, 6, 8. See Periodic Table. [From Greek osmē, smell (from the strong odor of osmium tetroxide).]osmium (ˈɒzmɪəm) n (Elements & Compounds) a very hard brittle bluish-white metal occurring with platinum and alloyed with iridium in osmiridium: used to produce platinum alloys, mainly for pen tips and instrument pivots, as a catalyst, and in electric-light filaments. Symbol: Os; atomic no: 76; atomic wt: 190.2; valency: 0 to 8; relative density: 22.57; melting pt: 3033±30°C; boiling pt: 5012±100°C[C19: from Greek osmē smell, so called from its penetrating odour]os•mi•um (ˈɒz mi əm) n. a hard, heavy, metallic element, densest of the known elements, able to form compounds with a valence of eight: used chiefly as a catalyst, in alloys, and in the manufacture of electric-light filaments. Symbol: Os; at. wt.: 190.2; at. no.: 76; sp. gr.: 22.57. [1795–1805; < New Latin = Greek osm(ḗ) smell + New Latin -ium -ium2; so named from the penetrating odor of one of its oxides] os·mi·um (ŏz′mē-əm) Symbol Os A hard, brittle, bluish-white metallic element. Osmium is the densest naturally occurring element. It is used to make very hard alloys for fountain pen points and electrical contacts. Atomic number 76. See Periodic Table.ThesaurusNoun | 1. | osmium - a hard brittle blue-grey or blue-black metallic element that is one of the platinum metals; the heaviest metal knownatomic number 76, Osmetal, metallic element - any of several chemical elements that are usually shiny solids that conduct heat or electricity and can be formed into sheets etc. | Translations
osmiumenUK
osmium (ŏz`mēəm), metallic chemical element; symbol Os; at. no. 76; at. wt. 190.23; m.p. 3,045±30°C;; b.p. 5,027±100°C;; sp. gr. 22.57 at 20°C;; valence usually +0 to +8. Osmium is a very hard, brittle, lustrous bluish-white metal with a close-packed hexagonal crystalline structure. It immediately precedes iridium in Group 8 of the periodic tableperiodic table, chart of the elements arranged according to the periodic law discovered by Dmitri I. Mendeleev and revised by Henry G. J. Moseley. In the periodic table the elements are arranged in columns and rows according to increasing atomic number (see the table entitled ..... Click the link for more information. . The measured densities of osmium and iridium indicate that osmium is slightly more dense than iridium, and osmium is generally credited as the heaviest element. Osmium does not oxidize readily in air except when heated or in powdered form; it then forms the unpleasant smelling, highly toxic tetroxide, OsO4. The tetroxide is used in microscopy as a stain, in fingerprint detection, and as a catalyst. Osmium is not affected by common acids but is oxidized to the tetroxide by hot nitric acid, hot sulfuric acid, or aqua regia. Osmium reacts with fluorine or chlorine gas at high temperatures to give the tetrafluoride or tetrachloride. In addition to the valences noted above, osmium assumes other valences between 0 and +8 in various compounds. Osmium is found in platinum ores and in the mineral osmiridium. It is recovered commercially as a byproduct of the refining of nickel ores mined near Sudbury, Ont., Canada. The metal is used largely for the production of hard alloys for use in fountain pen points, phonograph needles, and instrument bearings. Osmium was discovered by Smithson Tennant in 1804 in a residue left after dissolving crude platinum in aqua regia.Osmium Os, a chemical element in group VIII of the Mendeleev periodic system. Atomic number, 76; atomic weight, 190.2. One of the platinum metals. osmium[′äz·mē·əm] (chemistry) A chemical element, symbol Os, atomic number 76, atomic weight 190.2. (metallurgy) A hard white metal of rare natural occurrence. osmium a very hard brittle bluish-white metal occurring with platinum and alloyed with iridium in osmiridium: used to produce platinum alloys, mainly for pen tips and instrument pivots, as a catalyst, and in electric-light filaments. Symbol: Os; atomic no.: 76; atomic wt.: 190.2; valency: 0 to 8; relative density: 22.57; melting pt.: 3033?30?C; boiling pt.: 5012?100?C osmiumenUK
osmium (Os) [oz´me-um] a chemical element, atomic number 76, atomic weight 190.2. (See Appendix 6.)os·mi·um (Os), (oz'mē-ŭm), A metallic element of the platinum group, atomic no. 76, atomic wt. 190.2. [G. osmē, smell, because of the strong odor of the tetroxide] os·mi·um (oz'mē-ŭm) A metallic element of the platinum group, atomic no. 76, atomic wt. 190.2. os·mi·um (Os) (oz'mē-ŭm) A metallic element of the platinum group. MedicalSeeo/sosmiumenUK Related to osmium: osmium tetroxideSynonyms for osmiumnoun a hard brittle blue-grey or blue-black metallic element that is one of the platinum metalsSynonymsRelated Words |