PERIODIC ELEMENT
Be (Beryllium)

 



Atomic number : 4
Atomic mass : .9.01218 g.mol-1
Electronegativity according to Pauling : 1.5
Density : 1.86 g.cm-3
Melting point : 1280 °C
Boiling point : 2970 °C
Vanderwaals radius : unknown
Ionic radius : unknown
Isotopes : 1
Electronic shell : 1s2 2s2 or [He] 2s2
Energy of first ionisation : 899.2 kJ.mol-1
Energy of second ionisation : 1757 kJ.mol-1
Standard potential : - 1.70 V
Discovered by : Abbé René-Just Hauy in 1798
 
Atomic Structure Uses (spacecraft, missiles, aircraft)