4Be9.012
Alkaline Earth Metals-block
Beryllium
Element 4 on the periodic table, symbol Be, group 2, period 2.
Beryllium is a chemical element with symbol Be and atomic number 4. It is created through stellar nucleosynthesis and is a relatively rare element in the universe. It is a divalent element which occurs naturally only in combination with other elements in minerals.
Appearance: white-gray metallic
Properties
- Atomic Number
- 4
- Atomic Mass
- 9.0122 u
- Group
- 2
- Period
- 2
- Block
- s-block
- Category
- Alkaline Earth Metal
- State at 25 °C
- Solid
- Melting Point
- 1,560 K · 1,286.9 °C
- Boiling Point
- 2,742 K · 2,468.9 °C
- Density
- 1.85 g/cm³
- Atomic Radius
- 105 pm
- Electronegativity
- 1.57
- Oxidation States
- +2
- Abundance in Crust
- 2.8 mg/kg
- Discovered
- 1798
- Discovered By
- Louis Nicolas Vauquelin
Electron Configuration
[He] 2s2
1s2 2s2
Ionisation Energies (kJ/mol)
- 1. 899.5
- 2. 1,757.1
- 3. 14,848.7
- 4. 21,006.6
Elements near Beryllium
Elements in the same group share the number of outer electrons and behave in similar ways. Elements in the same period share a shell, so they change steadily from left to right.