Argon has an atomic number of 18, meaning each atom contains 18 protons in its nucleus.
The standard atomic weight of argon is 39.948 u (unified atomic mass units).
Argon is classified as a noble gas.
Argon is a gas at 20 Β°C (68 Β°F).
The melting point of argon is -189.35 Β°C / 83.8 K.
The boiling point of argon is -185.85 Β°C / 87.3 K.
The density of argon is 1.63e-3 g/cmΒ³ (20Β°C).
The electron configuration of argon is [Ne] 3s2 3p6.
Argon was discovered in 1894 by Lord Rayleigh and William Ramsay.
Argon is a stable element with no naturally occurring radioactive isotopes.
No known biological role.
Argon is used for: Welding gas; Lighting; Scientific instruments.