By Georges Urbain; Dirk Coster and George de Hevesy; Anton Eduard van Arkel and Jan Hendrik de Boer.
Abundance in Earth's crust
0.00033%
Abundance in Universe
7 * 10-8%
Type
Natural, but very rare
Hazards
Non-toxic, but powdered form is pyrophoric and can ignite spontaneously in air.
General properties
Group
4
Period
6
Block
d
Atomic weight
178.49
Category
Transition metal
Colour
Radioactive
No
Crystal structure
Simple hexagonal
Physical properties
Phase
Solid
Density
13.31 g/cm³
Melting point
2,506 K (2,233 °C)
Boiling point
4,876 K (4,603 °C)
Heat of fusion
25.5 kJ/mol
Heat of vaporization
630 kJ/mol
Specific heat capacity
0.144 J/g-K
Electron properties
Electrons per shell
2, 8, 18, 32, 10, 2
Electron configuration
[Xe] 4f14 5d2 6s2
Atomic properties
Atomic radius
159 pm
Covalent radius
175 pm
Electronegativity
1.3 (Pauling scale)
Ionization potential
6.8251 eV
Atomic volume
13.6 cm³/mol
Thermal conductivity
Oxidation states
2, 3, 4
Hafnium (Hf) is a metal and an element amongst the transition metals. Its atomic number is 72. It is a rare element in the Earth's crust, and is similar to tungsten. In nature, it is found with other elements.
