Atomic Number 72     Atomic Mass 178.49     Density 13.31 g/mL

State solid     Color grey steel     Electronegativity 1.5

Melting Point 2227°C     Boiling Point 4602°C

Natural Isotopes Hf-174 0.162%   Hf-176 5.206%   Hf-177 18.606%
                           Hf-178 27.297%   Hf-179 13.629%   Hf-180 35.100%

Abbreviated Electron Configuration [Xe] 4f¹⁴ 5d² 6s²

Discovered by Dirk Coster and Georg von Hevesy in 1923.