Information

Argon (Ar) properties


Atomic mass, symbol and atomic number

argon is a naturally occurring element with the elementary symbol Ar and the atomic number 18. In the periodic table it stands with an atomic mass of 39,948 u in the 8th main group. The chemical element discovered by William Ramsay in 1895 is not radioactive and is in a gaseous state at room temperature.

Characteristics: argon

General
Chemical element:argon
Symbol:Ar
Atomic number:18
Group:Noble gas group
Period:3
Block:p-block
Series:noble gases
Appearance:colorless
explorers:William Ramsay
Year of discovery:1895
Atomic properties
Atomic mass:39,948 u
Atomic radius:??? pm
Covalent radius:106 pm
Van der Waals radius:188 pm
Electron configuration:Ne 3s2 3p6
ionization:1520.8 kJ / mol
Physical Properties
Physical state:gaseous
Density:???
Crystal structure:cubic
Magnetism:diamagnetic
molar volume:22,56 · 10-6 m3/ mol
Mohs hardness:/
Melting point:-189 ° C
Boiling point:-186 ° C
Heat of fusion:1.18 kJ / mol
Heat of vaporization:6.52 kJ / mol
Thermal conductivity:0.017 W
Chemical properties
electronegativity:unknown

Did you know that ...

  • Bulbs contain a mixture of nitrogen and argon?
  • the earth's atmosphere consists of about 1% argon?
  • the name "argon" can be derived from the Greek (= "lazy") and alludes to the low-reaction properties of argon?
  • Argon is a colorless gas?