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Niobium |
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Pípè | /naɪˈoʊbiəm/ (ny-OH-bee-əm) |
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Ìhànsójú | gray metallic, yellowish when oxidized |
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Ìwúwo átọ̀mù Ar, std(Nb) | 92.90637(1)[1] |
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Niobium ní orí tábìlì àyè |
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Nọ́mbà átọ̀mù (Z) | 41 |
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Ẹgbẹ́ | group 5 |
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Àyè | àyè 5 |
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Àdìpọ̀ | Àdìpọ̀-d |
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Ẹ̀ka ẹ́límẹ́ntì | Transition metal |
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Ìtò ẹ̀lẹ́ktrọ́nù | [Kr] 4d4 5s1 |
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Iye ẹ̀lẹ́ktrọ́nù lórí ìpele kọ̀ọ̀kan | 2, 8, 18, 12, 1 |
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Àwọn ohun ìní ara |
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Ìfarahàn at STP | solid |
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Ìgbà ìyọ́ | 2750 K (2477 °C, 4491 °F) |
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Ígbà ìhó | 5017 K (4744 °C, 8571 °F) |
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Kíki (near r.t.) | 8.57 g/cm3 |
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Heat of fusion | 30 kJ/mol |
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Heat of | 689.9 kJ/mol |
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Molar heat capacity | 24.60 J/(mol·K) |
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pressure
P (Pa)
|
1
|
10
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100
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1 k
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10 k
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100 k
|
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at T (K)
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2942
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3207
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3524
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3910
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4393
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5013
|
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Atomic properties |
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Oxidation states | −3, −1, +1, +2, +3, +4, +5 Àdàkọ:Infobox element/symbol-to-oxidation-state/comment |
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Electronegativity | Pauling scale: 1.6 |
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Atomic radius | empirical: 146 pm |
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Covalent radius | 164±6 pm |
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Spectral lines of niobium |
Other properties |
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Natural occurrence | primordial |
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Crystal structure | (bcc) |
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Speed of sound thin rod | 3480 m/s (at 20 °C) |
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Thermal expansion | 7.3 µm/(m·K) |
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Thermal conductivity | 53.7 W/(m·K) |
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Electrical resistivity | 152 n Ω·m (at 0 °C) |
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Magnetic ordering | paramagnetic |
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Young's modulus | 105 GPa |
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Shear modulus | 38 GPa |
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Bulk modulus | 170 GPa |
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Poisson ratio | 0.40 |
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Mohs hardness | 6.0 |
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Vickers hardness | 1320 MPa |
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Brinell hardness | 736 MPa |
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CAS Number | 7440-03-1 |
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Main isotopes of niobium |
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Àdàkọ:Category-inline | references |