Actinium

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General Properties
Atomic number Predicted atomic mass Half life of main isotope Electron Configuration First discovered
89 227amu Around 21.8 years [Rn] 6d1 7s2 1899
General Properties
Atomic number 89
Predicted atomic mass 227amu
Half life of common isotope Around 21.8 years
Electron Configuration [Rn] 6d1 7s2
First discovered 1899

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Description and uses

Actinium is the 89th element of the periodic table. It was discovered in 1899 by Andrew Debierne, when he extracted it from pitchblende, an ore of uranium. Its longest living isotope is 227Ac, with a half life of around 21.8 years.

T&C