CAS Number7440-14-4
PubChem CID6328144
Atomic Radius-
Atomic Volume45.2
Atomic Weight[226]
Boiling Point1,737
Bulk Modulus
CategoryAlkaline earth metals
Crystal StructureBody Centered Cubic
Covalent Radius221
Electrical Resistivity
Electron Configuration[Rn] 7s2
Electrons per shell2, 8, 18, 32, 18, 8, 2
Heat of Fusion8
Heat of Vaporization125
Ionization Potential5.278
Magnetic Ordering
Magnetic Susceptibility
Mass Number88
Melting Point700
Atomic Number226
Oxidation States2
Poisson Ratio
Shear Modulus
Specific Heat Capacity-
Thermal Conductivity0.186
Van der Waals radius
Young's Modulus
Abundance in Earth's crust9.9×10-12%
Abundance in Universena
Ra Radium 88 (226) 2 7 s 88 700.0 1140.0 [Rn] 7s2 2 8 18 32 18 8 2 5.0 9.9E-12% Silver Cubic: Body centered 0.9 {"1":"509.3","2":"979.0"} 509 2 2.33 45.2 8.37 136.82 0.094 18.6 1 1.59×1033y AlphaEmission Solid, Conductor, AlkalineEarthMetal, Metal, Radioactive, Natural RAY-di-em Silvery-white metal. Intensely radioactive. Used in treating cancer because of the gamma rays it gives off. Found in uranium ores at 1 part per 3 million parts uranium. 5_I6vj-lXNM Radium
In 1911, Georges Urbain claimed to have found the element in rare-earth residues which was shown later to be a mixture of already discovered lanthanides.

Dirk Coster and George de Hevesy found it by X-ray spectroscopic analysis in Norwegian zircon in 1922.

Anton Eduard van Arkel and Jan Hendrik de Boer were the first to prepare metallic hafnium by passing hafnium tetra-iodide vapor over a heated tungsten filament in 1924. From Hafinia, the Latin name for Copenhagen 88 1898 Pierre and Marie Curie France From the Latin word "radius" meaning "ray"

Isotopes of Hafnium

Standard Atomic Weight


Stable Isotopes

Unstable Isotopes

202Ra 203Ra 204Ra 205Ra 206Ra 207Ra 208Ra 209Ra 210Ra 211Ra 212Ra 213Ra 214Ra 215Ra 216Ra 217Ra 218Ra 219Ra 220Ra 221Ra 222Ra 223Ra 224Ra 225Ra 226Ra 227Ra 228Ra 229Ra 230Ra 231Ra 232Ra 233Ra 234Ra

Hafnium is considered to be non-toxic
In powdered form, hafnium is pyrophoric and can ignite spontaneously in air
Hafnium oxide-based compounds are being introduced into silicon-based chips to produce smaller, more energy efficient and performance packed processors.

Most of the hafnium produced is used in the production of control rods for nuclear reactors.

Hafnium is also used in photographic flash bulbs, light bulb filaments, and in electronic equipment as cathodes and capacitors.