Actinium (Ac) — Element 89: Properties & Data | Aladdin Scientific

Actinium(Ac) — Element 89

Actinide · Group · Period 7

Actinium (Ac) is a actinide with atomic number 89 and atomic mass 227.028. It has melting point 1324 K (1051 °C), boiling point 3471 K (3198 °C), density 10.07 g/cm³. It sits in period 7 of the periodic table and was discovered in 1899.

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Key facts

Atomic mass227.0277 u
Electron configuration[Rn]7s2 6d1
Oxidation states+3
Electronegativity (Pauling)1.1
Atomic radius (van der Waals)260 pm
Ionization energy5.17 eV
Melting point1324 K
Boiling point3471 K
Density10.07 g/cm³
Standard stateSolid
Year discovered1899

Preguntas frecuentes

What is the electron configuration of actinium?

The ground-state electron configuration of actinium is [Rn]7s2 6d1.

What group and period is actinium in?

Actinium (Ac) is in period 7 (actinide series) of the periodic table, classified as a actinide.

What is the melting point of actinium?

Actinium melts at 1324 K (1051 °C).

What is the standard state of actinium?

Actinium is a solid at standard temperature and pressure.

Sobre estos datos: property values compiled from IUPAC Standard Atomic Weights (2021), the NIST Atomic Spectra Database, and PubChem. Curated by the Aladdin Scientific technical team. Last reviewed: .

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