 |
| Hafnium |
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| Pípè | /ˈhæfniəm/ (HAF-nee-əm) |
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| Ìhànsójú | steel grey |
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| Ìwúwo átọ̀mù Ar, std(Hf) | 178.486(6)[1] |
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| Hafnium ní orí tábìlì àyè |
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|
| Nọ́mbà átọ̀mù (Z) | 72 |
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| Ẹgbẹ́ | group 4 |
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| Àyè | àyè 6 |
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| Àdìpọ̀ | Àdìpọ̀-d |
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| Ẹ̀ka ẹ́límẹ́ntì | Transition metal |
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| Ìtò ẹ̀lẹ́ktrọ́nù | [Xe] 4f14 5d2 6s2 |
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| Iye ẹ̀lẹ́ktrọ́nù lórí ìpele kọ̀ọ̀kan | 2, 8, 18, 32, 10, 2 |
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| Àwọn ohun ìní ara |
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| Ìfarahàn at STP | solid |
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| Ìgbà ìyọ́ | 2506 K (2233 °C, 4051 °F) |
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| Ígbà ìhó | 4876 K (4603 °C, 8317 °F) |
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| Kíki (near r.t.) | 13.31 g/cm3 |
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| when liquid (at m.p.) | 12 g/cm3 |
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| Heat of fusion | 27.2 kJ/mol |
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| Heat of | 571 kJ/mol |
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| Molar heat capacity | 25.73 J/(mol·K) |
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pressure| P (Pa) | 1 | 10 | 100 | 1 k | 10 k | 100 k |
|---|
| at T (K) | 2689 | 2954 | 3277 | 3679 | 4194 | 4876 |
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|
| Atomic properties |
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| Oxidation states | −2, +1, +2, +3, +4 Àdàkọ:Infobox element/symbol-to-oxidation-state/comment |
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| Electronegativity | Pauling scale: 1.3 |
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| Atomic radius | empirical: 159 pm |
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| Covalent radius | 175±10 pm |
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 Color lines in a spectral rangeSpectral lines of hafnium |
| Other properties |
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| Natural occurrence | primordial |
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| Crystal structure | hexagonal |
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| Speed of sound thin rod | 3010 m/s (at 20 °C) |
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| Thermal expansion | 5.9 µm/(m·K) (at 25 °C) |
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| Thermal conductivity | 23.0 W/(m·K) |
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| Electrical resistivity | 331 n Ω·m (at 20 °C) |
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| Magnetic ordering | paramagnetic[2] |
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| Young's modulus | 78 GPa |
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| Shear modulus | 30 GPa |
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| Bulk modulus | 110 GPa |
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| Poisson ratio | 0.37 |
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| Mohs hardness | 5.5 |
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| Vickers hardness | 1760 MPa |
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| Brinell hardness | 1700 MPa |
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| CAS Number | 7440-58-6 |
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| Main isotopes of hafnium |
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| Isotope | Abundance | Half-life (t1/2) | Decay mode | Product |
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| 172Hf | syn | 1.87 y | ε | 0.350 | 172Lu | | 174Hf | 0.162% | 2×1015 y | α | 2.495 | 170Yb | | 176Hf | 5.206% | 176Hf is stable with 104 neutrons | | 177Hf | 18.606% | 177Hf is stable with 105 neutrons | | 178Hf | 27.297% | 178Hf is stable with 106 neutrons | | 178m2Hf | syn | 31 y | IT | 2.446 | 178Hf | | 179Hf | 13.629% | 179Hf is stable with 107 neutrons | | 180Hf | 35.1% | 180Hf is stable with 108 neutrons | | 182Hf | syn | 9×106 y | β− | 0.373 | 182Ta |
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Àdàkọ:Category-inline
| references |
