NO. 099Actinide

Es

Einsteinium

Einsteinium is a synthetic actinide discovered in nuclear fallout. It is used only for research due to its extreme radioactivity and scarcity.

Crystal Structure

Face-centered cubic

Atomic Mass252 u

Density8.8 g/cm³

Melting Point1133 K

Boiling Point1269 K

Atomic Radius186 pm

Electronegativity1.3

Ionization Energy619 kJ/mol

Electron Affinity0 kJ/mol

Bonding TypeMetallic

Oxidation States2, 3

Acid/BaseBasic

ReactivityHigh

Electron Configuration

[Rn] 5f11 7s2

Discovered ByLawrence Berkeley Lab

Year1952

Known Isotopes

Es-252