Ac
89actinideGenerated with AI1 min read
Actinium
SymbolAc
Atomic Mass227
Actinium is a radioactive chemical element with symbol Ac (not to be confused with the abbreviation for an acetyl group) and atomic number 89, which was discovered in 1899. It was the first non-primordial radioactive element to be isolated. Polonium, radium and radon were observed before actinium, but they were not isolated until 1902.
Properties
- Phase: Solid
- Density: 10 g/cm³
- Melting Point: 1500 K
- Boiling Point: 3500 K