Einsteinium (Es)

Einsteinium

Einsteinium (Es) is an actinide in period 7. Its relative atomic mass is [252] and the molar mass of the atom is [252] g/mol.

Position in the tableBack to the full table →
Atomic number 99
Atomic mass [252] predicted
Molar mass [252] g/mol
Category Actinide Solid

Properties of einsteinium

Atomic number99
SymbolEs
Latin nameEinsteinium
Relative atomic mass[252]
Molar mass[252] g/mol
Group, period, block—, 7, f
CategoryActinide
State at 20 °CSolid
Electron configuration[Rn] 5f¹¹ 7s²
Electronegativity (Pauling)1.3

Electron configuration of einsteinium

Es
Bohr model (simplified)
Electrons per shell
K2L8M18N32O29P8Q2
Full notation

1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 4f¹⁴ 5s² 5p⁶ 5d¹⁰ 5f¹¹ 6s² 6p⁶ 7s²

Noble-gas notation

[Rn] 5f¹¹ 7s²

99 protons · 99 electrons

Formula and compounds of einsteinium

Simple substanceEseinsteinium

Molar mass of Es: [252] g/mol

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Frequently asked questions

The relative atomic mass of einsteinium is [252], so the molar mass of the atom is [252] g/mol.

Full: 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 4f¹⁴ 5s² 5p⁶ 5d¹⁰ 5f¹¹ 6s² 6p⁶ 7s². Noble-gas notation: [Rn] 5f¹¹ 7s².