Actinium (Ac)

Actinium (Ac)

Atomic Number: 89
Atomic Weight: 227
Melting Point: 1050
Boiling Point: 3200
Specific Gravity: 10.07
Valence(s): not known

Actinium was discovered in 1899 by Debierne. Actinium is found in nature associated with Uranium ores. This radioactive metal emits beta particles. After radioactive decay, it emits alpha particles. It is named after the Greek word aktinos, meaning ray. [LM] {RW}