89

Ac

Actinium
[ 227 ]
 Historical Information

Actinium was discovered by Andre Debierne in 1899 and independently by F. Giesel in 1902, both of whom obtained it while working on separation techniques for rare earth oxides.
Basic Information Shells
  • Name:Actinium
  • Symbol: Ac
  • Atomic number: 89
  • Atomic weight: [ 227 ]
  • Standard state: solid at 298 K
  • Group in periodic table:
  • Group name:actinoid
  • Period in periodic table: 7
  • Block in periodic table: f-block
  • Classification: Metallic
 Actinium
Uses Trivia
  • thermoelectric power
  • source of neutrons

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.