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Actinium (Ac): Fun Facts and Information About the Element


What is the symbol? Ac
What is the atomic number? 89
What is the atomic weight? 227
What is the melting point in Celsius? 1050
What is the boiling point in Celsius? 3200
What is the density (g/cm3)? 10.07
What year was it discovered? 1899
Who discovered the element? André-Louis Debierne
What group is the element in? 3
What is the electron configuration? [Rn] 6d1 7s2
What is the ionization energy? 5.17
What element category is it in? Actinoids

Where is Actinium Found?

Actinium-227, a decay product of uranium-235, is a beta emitter with a 21.6-year half-life.

What is Actinium Used For?

It is about 150 times as active as radium, making it of value in the production of neutrons.