Einsteinium (Es) — Element 99: Properties & Data | Aladdin Scientific
Einsteinium(Es) — Element 99
Einsteinium (Es) is a actinide with atomic number 99 and atomic mass 252.083. It has melting point 1133 K (860 °C). It sits in period 7 of the periodic table and was discovered in 1952.
Key facts
| Atomic mass | 252.0830 u |
|---|---|
| Electron configuration | [Rn]7s2 5f11 |
| Oxidation states | +3 |
| Electronegativity (Pauling) | 1.3 |
| Atomic radius (van der Waals) | 245 pm |
| Ionization energy | 6.42 eV |
| Melting point | 1133 K |
| Standard state | Solid |
| Year discovered | 1952 |
Frequently asked questions
What is the electron configuration of einsteinium?
The ground-state electron configuration of einsteinium is [Rn]7s2 5f11.
What group and period is einsteinium in?
Einsteinium (Es) is in period 7 (actinide series) of the periodic table, classified as a actinide.
What is the melting point of einsteinium?
Einsteinium melts at 1133 K (860 °C).
What is the standard state of einsteinium?
Einsteinium is a solid at standard temperature and pressure.
Related elements
About this data: 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: .