89Ac

Actinium

Actinide

Properties of Actinium

Atomic number (Z)
89
Symbol
Ac
Name
Actinium
Atomic mass
227 u
Period
7
Group
3
Family
Actinides (f-block)
Classification
Actinide
Electron configuration
[Rn] 6d¹ 7s²

About Actinium

Actinium is a chemical element with symbol Ac and atomic number 89 (atomic mass of about 227 u). It is classified as a actinide on the periodic table.

On the periodic table, Actinium is located in period 7, in group 3, belonging to the actinides (f-block) family. An element's position reveals trends in its properties, such as atomic radius, electronegativity and metallic character.

The electron configuration of Actinium is [Rn] 6d¹ 7s², which determines how it forms chemical bonds and takes part in reactions.

External references