Symbol	Hf	Atomic radius: pm	156	Fusion: kJ/Mole	27.2
Name	Hafnium	Ionic radius: pm	(+4)83	Boiling point: °C	4603
Atomic number	72	Electron affinity	~0	Melting point: °C	2233
Atomic weight	178.5	1st  ion potential	6.83	Specific Heat Cap: J/(g K)	0.14
Classification	Trans metal	Natural form	Solid	Thermal Cond: W/(cm K)	0.23
Configuration	[Xe]4f145d26s2	Crystal structure	Hex	Electrical Cond	0.0312
Oxidation states	4	Density	13.3	Abundance: mg/kg-crust	3
Electronegativity	1.3	Vaporization: kJ/Mole	661.1
Hafnium was discovered in 1923 by Dirk Coster and George Charles de Hevesy.			Uses - nuclear control rods, gas-filled and incandescent lamps