89
Ac
227
Actinium
Element 89 · 227 u · f-block
actinide
A highly radioactive metal that glows blue in the dark. Used in neutron sources and targeted cancer therapy research.
Phase (STP)
Solid
Melting Point
1050 °C
Boiling Point
3198 °C
Density
10.07 g/cm³
Electronegativity
1.1
Atomic Radius
195 pm
Ionization Energy
499 kJ/mol
Electron Affinity
34 kJ/mol
Discovered
1899 · Andre-Louis Debierne
Electron Configuration
[Rn] 6d1 7s2
Electron Orbitals
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