← Periodic Table
99
f🧱
Es
252.0000

Einsteinium

Actinide

Atomic Properties

Atomic Number
99
Atomic Mass
252.0000 u
Electron Configuration
[Rn] 5f11 7s2
Electronegativity
1.30
Block
f-block
Group
Period
7

🌡 Physical Properties

Phase (STP)
solid
Melting Point
1133.00 K
Boiling Point
1269.00 K
Density
8.8400 g/cm³

About Einsteinium

Named after Albert Einstein; discovered in hydrogen bomb debris.

🔬 Isotopes of Einsteinium

Einsteinium has 0 naturally occurring isotopes, plus 1 notable radioactive isotope.

IsotopeMass NumberAtomic Mass (u)AbundanceType
252Es252252.08298Radioactive

Data source: NIH PubChem (aggregated from IUPAC, NIST)