Revision as of 09:56, 11 February 2021 by imported>Double sharp
[[Category:Template:Pagetype with short description]]
Hafnium, 72Hf |
| Hafnium |
|---|
| Pronunciation | (Template:Respell) |
|---|
| Appearance | steel gray |
|---|
| Standard atomic weight Ar, std(Hf) | Template:Val[1] |
|---|
| Hafnium in the periodic table |
|---|
|
|
| Atomic number (Z) | 72 |
|---|
| Group | group 4 |
|---|
| Period | period 6 |
|---|
| Block | d-block |
|---|
| Electron configuration | [Xe] 4f14 5d2 6s2 |
|---|
| Electrons per shell | 2, 8, 18, 32, 10, 2 |
|---|
| Physical properties |
|---|
| Phase at STP | solid |
|---|
| Melting point | 2506 K (2233 °C, 4051 °F) |
|---|
| Boiling point | 4876 K (4603 °C, 8317 °F) |
|---|
| Density (near r.t.) | 13.31 g/cm3 |
|---|
| when liquid (at m.p.) | 12 g/cm3 |
|---|
| Heat of fusion | 27.2 kJ/mol |
|---|
| Heat of vaporization | 648 kJ/mol |
|---|
| Molar heat capacity | 25.73 J/(mol·K) |
|---|
Vapor pressure
| P (Pa)
|
1
|
10
|
100
|
1 k
|
10 k
|
100 k
|
| at T (K)
|
2689
|
2954
|
3277
|
3679
|
4194
|
4876
|
|
| Atomic properties |
|---|
| Oxidation states | −2, 0, +1, +2, +3, +4 (an amphoteric oxide) |
|---|
| Electronegativity | Pauling scale: 1.3 |
|---|
| Ionization energies | - 1st: 658.5 kJ/mol
- 2nd: 1440 kJ/mol
- 3rd: 2250 kJ/mol
-
|
|---|
| Atomic radius | empirical: 159 pm |
|---|
| Covalent radius | 175±10 pm |
|---|
| Spectral lines of hafnium |
| Other properties |
|---|
| Natural occurrence | primordial |
|---|
| Crystal structure | hexagonal close-packed (hcp) |
|---|
| Speed of sound thin rod | 3010 m/s (at 20 °C) |
|---|
| Thermal expansion | 5.9 µm/(m·K) (at 25 °C) |
|---|
| Thermal conductivity | 23.0 W/(m·K) |
|---|
| Electrical resistivity | 331 nΩ·m (at 20 °C) |
|---|
| Magnetic ordering | paramagnetic[2] |
|---|
| Magnetic susceptibility | +75.0·10−6 cm3/mol (at 298 K)[3] |
|---|
| Young's modulus | 78 GPa |
|---|
| Shear modulus | 30 GPa |
|---|
| Bulk modulus | 110 GPa |
|---|
| Poisson ratio | 0.37 |
|---|
| Mohs hardness | 5.5 |
|---|
| Vickers hardness | 1520–2060 MPa |
|---|
| Brinell hardness | 1450–2100 MPa |
|---|
| CAS Number | 7440-58-6 |
|---|
| History |
|---|
| Naming | after Hafnia. Latin for: Copenhagen, where it was discovered |
|---|
| Prediction | Dmitri Mendeleev (1869) |
|---|
| Discovery and first isolation | Dirk Coster and George de Hevesy (1922) |
|---|
| Main isotopes of hafnium |
|---|
|
|
Category: Hafnium | references |
[[Category:Infobox templates|Template:Remove first word]]
References
These references will appear in the article, but this list appears only on this page.
Lua error: Internal error: The interpreter has terminated with signal "24".