All chemical elements

Symbol

Ar

Atomic number

18

Chemical property

Noble gas

Origin o the name

the Greek argos, 'idle'

Group

18

Period

3

Atomic weight (u)

39.948

Atomic weight uncertainty (u)

0.001

Density (g/cm³)

0.001784

Melting point (K)

83.8

Boiling point (K)

87.3

Heat capacity (J/(g·K))

0.52

Abundance in earth's crust (mg/kg)

3.5