PERIODIC ELEMENT
Hf (Hafnium)

 



Atomic number : 72
Atomic mass : 178.49 g.mol-1
Electronegativity according to Pauling : 1.3
Density : 13.07 g.cm-3 at 20 °C
Melting point : 2200 °C
Boiling point : 5200 °C
Vanderwaals radius : 0.161 nm
Ionic radius : 0.075 nm
Isotopes : 10
Electronic shell : [Xe] 4f14 5d26s2
Energy of first ionisation : 530 kJ.mol-1
Energy of second ionisation : 1425.5 kJ.mol-1
Energy of third ionisation : 2244.3 kJ.mol-1
Energy of fourth ionisation : 3207.5 kJ.mol-1
Standard potential : - 1.68 V (Hf2+ / Hf)
Discovered by : Dirk Coster in 1923
 
Atomic Structure Uses (nuclear reactors)