Os
Osmium
Atomic number: 76Mass: 190.23 uCategory: Transition Metal
About Osmium
Osmium is the densest naturally occurring element. It is a hard, brittle, bluish-white transition metal. It has a pungent smell from osmium tetroxide, which is highly toxic. It belongs to the platinum group.
Properties
Period
6
Group
8
Block
D
Category
Transition Metal
Electronegativity
2.20 (Pauling)
Ionization Energy
840 kJ/mol
Melting Point
3306 K (3033°C)
Boiling Point
5285 K (5012°C)
Density
22.59 g/cm³
Oxidation States
+4, +8
Electron Configuration
1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 4f¹⁴ 5s² 5p⁶ 5d⁶ 6s²
[Xe] 4f¹⁴ 5d⁶ 6s²
Shell 1:2e⁻
Shell 2:8e⁻
Shell 3:18e⁻
Shell 4:32e⁻
Shell 5:14e⁻
Shell 6:2e⁻
Real-World Uses
Fountain pen tips
Electrical contacts
Fingerprint detection chemicals
Microscopy staining
Alloys
Fun Fact
Osmium is the densest element in the universe — a cube of it the size of a sugar cube would weigh as much as a full water bottle!