Radon (Rn)

Radon (Rn)

Atomic Number: 86
Atomic Weight: (222)
Melting Point: -71.0
Boiling Point: -61.8
Specific Gravity: 4.4 (liquid) 4.0 (solid)
Valence(s): 0

Radon was discovered by Dorn in 1900, isolated by Ramsay and Gray in 1908 and has been called Radon since 1923. Radon is radioactive and is present in the atmosphere in minute quantities. It is sometimes used therapeutically by a few hospitals to treat patients. [LM] {RW}