99Es
Element 99
Einsteinium
Actinides
Einsteinium is a synthetic element with symbol Es and atomic number 99.
Key data
- Atomic number
- 99
- Atomic mass
- 252.000 u
- Group / Period
- 3 / 7
- Block
- f-block
- Phase at STP
- Solid
- Density
- 8.84 g/cm³
- Melting point
- 859.9 °C
- Boiling point
- 995.9 °C
- Electron configuration
- [Rn] 5f11 7s2
Common uses
- •Research only
- •Extremely rare
- •Synthesized in 1952 H-bomb test
Discovery
Year: 1952
Discovered by: Lawrence Berkeley National Laboratory
Frequently asked questions
What is the atomic number of Einsteinium?
Einsteinium has atomic number 99. Its symbol is Es and its atomic mass is 252 u.
What category of element is Einsteinium?
Einsteinium is classified as actinides. It sits in group 3, period 7 of the periodic table.
What is Einsteinium used for?
Common uses of Einsteinium include: Research only, Extremely rare, Synthesized in 1952 H-bomb test.
When was Einsteinium discovered?
Einsteinium was discovered in 1952 by Lawrence Berkeley National Laboratory.
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