Argon (Ar)
"Captain Inert, the laziest of heroes, who refuses to react and protects hot-headed filaments in lightbulbs."
A memorable persona to anchor Ar in your mind.
1.784
Grams per cm³
-189.34
Celsius (°C)
188
Radius (pm)
Daily Life Link
The gas inside an old-fashioned incandescent light bulb.
Discovery & History
Year Discovered
1894
Discovered By
Lord Rayleigh & William Ramsay
Origin of Name
"The name is derived from the Greek, ''argos'', meaning idle."
Technical Properties
Atomic Mass
39.95 u
Standard State
gas
Boiling Point
-185.848°C
Electron Configuration
[Ne] 3s23p6
1st Ionization Energy
15.76 eV
Electron Affinity
N/A
Oxidation States
"A colorless, odorless, tasteless inert gas."
Did You Know?
Its name comes from the Greek word 'argos', meaning 'lazy' or 'inactive', due to its chemical inertness.
It is the third-most abundant gas in Earth's atmosphere, after nitrogen and oxygen.
Incandescent light bulbs are filled with argon to prevent the hot tungsten filament from burning out.
Double-paned windows often have argon gas sealed between the panes to act as a thermal insulator.