Stable isotope Hafnium (Hf)

 
Isotope Z(p) N(n) Atomic Mass Natural Abundance Enrichment Level Chemical Form
Hf-174 72 102 173.940042 0.162% 13.46% Oxide
Hf-176 72 104 175.941406 5.260% 84.60% Oxide
Hf-177 72 105 176.943220 18.606% 85.40% Oxide
Hf-178 72 106 177.943698 27.297% 92.40% Oxide
Hf-179 72 107 178.945815 13.629% 75.00% Oxide
Hf-180 72 108 179.946549 35.100% ≥94.60% Oxide

Properties of Hafnium

Name Hafnium
Symbol Hf
Atomic number 72
Atomic weight 178.49
Standard state Solid at 298 ºK
CAS Registry ID 7440-58-6
Group in periodic table 4
Group name None
Period in periodic table 6
Block in periodic table d-block
Color Gray steel
Classification Metallic
Melting point 2233 °C
Boiling point 4602 °C
Vaporization point 2233 ºC
Thermal conductivity 23.0 W/(m·K) at 298.2 ºK
Electrical resistivity 35.1 µΩ·cm at 25 ºC
Electronegativity 1.3
Specific heat 0.14 kJ/kg K
Heat of vaporization 630 kJ·mol-1 at 4602 ºC
Heat of fusion 25.5 kJ·mol-1 mole
Density of liquid 12 g/cm3 at 2233 °C
Density of solid 13.31 g/cm3
Electron configuration [Xe]4f145d26s2
Atomic radius 1.442 Å
Common oxidation state +4 (also exhibits oxidation states +2 and +3)