99Es252
Einsteinium
Actinide · element 99 · f-block (shown below the main table)
Quick facts
| Symbol | Es |
|---|---|
| Atomic number | 99 |
| Relative atomic mass | 252 |
| Category | Actinide |
| Position | f-block (shown below the main table) |
| State at 20 °C | Solid |
| Melting point | 860 °C |
| Boiling point | — |
| Density | — |
| Electronegativity | 1.3 |
| Electron configuration | [Rn] 5f11 7s2 |
About Einsteinium
Einsteinium has the symbol Es and atomic number 99, which means every einsteinium atom has 99 protons in its nucleus and, in a neutral atom, 99 electrons. At room temperature it is a solid.
Actinides are the second row of the f-block. They are all radioactive, and only a few (like uranium and thorium) occur naturally in large amounts.
It melts at 860 °C.
Explore it
See where einsteinium sits, and drag the temperature slider to watch it melt and boil, on the interactive periodic table. Practise with quizzes on OmniEx.