To share this content with an AI assistant
4Be9.01218
Beryllium
Alkaline earth metalsBlock sPeriod 2Group 2solid at 20 °C
Configuration :[He] 2s²
Atomic mass :9.0121831 u
French :Béryllium
3D Bohr-model representation of the Beryllium atom (symbol Be, atomic number Z=4). Electron shell configuration: 2, 2 electrons.
Scroll to activate 3D
Bohr model · educational
Electron configuration
Full1s² 2s²
Short[He] 2s²
Valence electrons2
KLMNOPQ shells
K2
L2
Electronegativity
Pauling1.57
Allen1.576
Mulliken (eV)—
Atomic radii
Empirical105 pm
Calculated112 pm
Covalent96 pm
Van der Waals153 pm
Ionic radii (Shannon-Prewitt)
+245 pm
Successive ionisation energies
I₁899.5 kJ/mol
I₂1757.1 kJ/mol
I₃14848.7 kJ/mol
I₄21006.6 kJ/mol
Electron affinity—
Oxidation states
+1+2
Bold states = most common.