| Property | Value | Property | Value |
|---|---|---|---|
| Appearance | Shiny, brittle, bluish-white metal | ||
| Classification | Transition Metals | Density | 22.587 g/cm³ at STP |
| Boiling Point | 5281 K | Melting Point | 3306 K |
| Property | Value | Property | Value |
|---|---|---|---|
| Atomic Number | 76 | Atomic Mass | 190.233 |
| Van Der Waals Radius | 216 | Atomic Radius (empirical) | 135 |
| Property | Value | Property | Value |
|---|---|---|---|
| Electronegativity | 2.2 | Electron Affinity | 103.99 kJ/mol |
| Electron Configuration | 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d6 | ||
| Oxidation States | 8, 7, 6, 5, 4, 3, 2, 1, 0, -1, -2, -4 (mildly acidic) | ||
| Ionization Energies | Showing all 2 ionization energies.
| ||
In 1803, Smithson Tennant and William Hyde Wollaston identified osmium as a new element while analyzing an insoluble residue of platinum that was dissolved in aqua regia (a mixture of nitric and hydrochloric acids). Tennant named the element osmium after the Greek word osme, meaning “a smell” because of the ash and smoke produced by one of the isolated residues (osmium tetroxide).
At room temperature, osmium is a hard, brittle, shiny, bluish-white metal. It is highly durable when combined with another metal. Osmium is very reflective in ultraviolet light and absorbs hydrogen when in powdered form.
In small quantities, it can spontaneously form volatile and poisonous osmium tetroxide at room temperature.
Osmium alloys are used in high-wear applications where durability is important. Some example uses are fountain pen tips, instrument pivots, electrical contacts, and phonograph needles.
Osmium tetroxide is used in fingerprint detection and potassium osmate is an oxidant in organic synthesis.
An alloy of osmium is used in pacemakers and heart valves.
Osmium is the least abundant stable element in the Earth’s crust. It is found as a pure element or in iridium-osmium alloys. Within the crust, osmium is present in igneous deposits, impact craters, and nickel-copper deposits. South Africa, Russia, and Canada have significant sources of osmium.
Osmium is also produced as a by-product of the processing of platinum and nickel ores.