Osmium (Os)
"The Densest, the heaviest and most compact hero on the planet."
A memorable persona to anchor Os in your mind.
22.59
Grams per cm³
3033
Celsius (°C)
216
Radius (pm)
Daily Life Link
Osmium is found in the durable, non-wearing tip of a high-end fountain pen.
Discovery & History
Year Discovered
1803
Discovered By
Smithson Tennant
Origin of Name
"The name is derived from the Greek word ''osme'', meaning smell."
Technical Properties
Atomic Mass
190.23 u
Standard State
solid
Boiling Point
5008°C
Electron Configuration
[Xe] 4f145d66s2
1st Ionization Energy
8.7 eV
Electron Affinity
N/A
Oxidation States
"Osmium is a hard, brittle, bluish-white metal � the densest element."
Did You Know?
It is the densest naturally occurring element on Earth, approximately twice as dense as lead.
Its name comes from the Greek word 'osme', meaning 'smell', because its volatile oxide, osmium tetroxide, has a very sharp, unpleasant, chlorine-like odor.
Because it is extremely hard and wear-resistant, alloys of osmium are used to make the tips of high-end fountain pens, instrument pivots, and electrical contacts.
Osmium tetroxide is a powerful oxidizing agent and is used in chemical synthesis and as a stain for microscopy.