osmium

American  

[oz-mee-uhm] / ˈɒz mi əm /

noun

Chemistry.

1. a hard, heavy, metallic element having the greatest density of the known elements and forming octavalent compounds, as OsO 4 and OsF 8 : used chiefly as a catalyst, in alloys, and in the manufacture of electric-light filaments. Os; 190.2; 76; 22.57.

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osmium British  

/ ˈɒzmɪəm /

noun

1. 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

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osmium Scientific  

/ ŏz′mē-əm /

1. A hard, brittle, bluish-white metallic element that is the densest naturally occurring element. It is used to make very hard alloys for fountain pen points, electrical contacts, and instrument pivots. Atomic number 76; atomic weight 190.2; melting point 3,000°C; boiling point 5,000°C; specific gravity 22.57; valence 2, 3, 4, 8.

2. See Periodic Table

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Etymology

Origin of osmium

1795–1805; < New Latin < Greek osm ( ḗ ) smell + -ium -ium; named from the penetrating odor of one of its oxides

Example Sentences

Until now, many of these light-driven processes depended on ruthenium, osmium, or iridium -- elements that are costly, scarce, and create environmental concerns when mined.

From Science Daily

Catalysts incorporating osmium exhibited high activity due to the expanded electrochemical active surface area achieved through nanostructure formation.

From Science Daily

Two geoscientists advanced the theory in 2013, partially because the levels of iridium and osmium around the impact site were lower than should appear in an asteroid and more apt for a comet impact.

From Salon

They used details of the fossils themselves and ratios of osmium isotopes in clay, whose abundance over time has been previously charted.

From Scientific American

It is a shiny white metal in the same group as platinum, along with ruthenium, rhodium, osmium, and iridium.

From BBC