Name: actinium
Symbol: Ac
Atomic number: 89
Atomic weight: [ 227 ]
Group in periodic table:
Group name:
Period in periodic table: 7 (actinoid)
Block in periodic table: f-block
CAS registry ID: 7440-34-8
Actinium is dangerously radioactive. The chemical behaviour of actinium is similar to that of the rare earths, particularly lanthanum. It is found naturally in uranium ores and actinium is 150 times more radioactive than radium.