| Reactions of Osmium |
 Reactions with water |
| Osmium does not react with water under normal conditions. |
| Reactions with air |
| Osmium is largely immune to atmospheric attack. On heating with oxygen, osmium metal gives the rather volatile (melting point 30°C, boiling point 130°C) osmium(VIII) oxide, OsO4. Finely divided osmium metal gives off a characteristic smell of OsO4, a highly toxic compound.
|
Os(s) + 2O2(g) OsO4(s) |
| Reactions with halogens |
| Osmium reacts with excess of fluorine at 600°C and 400 atmosphere pressure to form osmium(VII) fluoride.
|
| 2Os(s) + 7F2(g)2OsF7(s) |
| Under milder conditions, the hexafluoride OsF6 is produced.
|
| Os(s) + 3F2(g)OsF6(s) |
| Osmium reacts with either chlorine or bromine with heating under pressure to form the tetrahalides osmium(IV) chloride or osmium(IV) bromide.
|
| Os(s) + 2Cl2(g)OsCl4(s) |
| Os(s) + 2Br2(g)OsBr4(s) |
Os(s)