Argon (Ar)

The third-most abundant gas in the Earth's atmosphere.

Its name comes from the Greek word for 'lazy' because it doesn't easily react.

Element properties

Atomic number
18
Symbol
Ar
Atomic mass
39.95 u
Category
Noble Gas
Period
3
Group
18
Block
p
State
Gas
Electron configuration
[Ne] 3s2 3p6
Electronegativity (Pauling)
Not available
Density
0.0017837 g/cm³
Melting point
-189.3 °C
Boiling point
-185.8 °C

Uses