Beryllium ( Be )

• Atomic number: 4
• Appearance: white-gray metallic
• Standard atomic weight: 9.012
• Group: group 2 (alkaline earth metals)
• Period: 2
• Electron configuration: 1s² 2s²
• Element category: alkaline earth metal
• Melting point: 1560 K
• Boiling point: 2742 K
• Sublimation point:
Standard Temperature ( 273.15 ) and Pressure ( 1 bar = 10⁵ Pa )
• Phase at STP: solid
• Density at STP:
• Heat of fusion: 12.2 kJ/mol
• Heat of vaporization: 292 kJ/mol
• Molar heat capacity: 16.443 kJ/(mol·K)
• Oxidation states: 0 +1 +2
• Electronegativity: Pauling scale: 1.57
• Covalent radius: 96 pm (1×10⁻¹² m)
• Van der Waals radius: 153 pm (1×10⁻¹² m)
• Crystal structure:
• Speed of sound: 12890 m/s (at 20 °C)
• Thermal expansion: 11.3 µm/(m·K)
• Thermal conductivity: 200 W/(m·K)