Actinium (Ac) is a chemical element belonging to the category Actinide metal, with atomic number 89 and atomic mass 227.0000 u. This sheet describes its fundamental properties, periodic position and physical characteristics.
Identity
- Name: Actinium
- Symbol: Ac
- Atomic number: 89
- Atomic mass: 227.0000 u
Position in the periodic table
- Group: 3
- Period: 7
- Category: Actinide metal
Physico-chemical properties
- Standard state: Solid
- Melting point: Characteristic melting point
- Density: Very high
- Electron configuration: [Rn] 6d¹ 7s²
Scientific description
Actinium is a chemical element with symbol Ac and atomic number 89. It belongs to the category of Actinide metal and occupies group 3 and period 7. Its standard atomic mass is 227.0000 u.