Cobalt
Lát'ọwọ́ Wikipedia, ìwé ìmọ̀ ọ̀fẹ́
| Cobalt |
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27Co
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| Ìhànsójú |
hard lustrous gray metal
 |
| Àwọn ìdámọ́ wíwọ́pọ̀ |
| Orúkọ, àmì-ìdámọ́, nọ́mbà |
cobalt, Co, 27 |
| Ẹ̀ka ẹ́límẹ̀nti |
transition metal |
| Ẹgbẹ́, àsìkò, àdìpò |
9, 4, d |
| Ìwúwo átọ́mù |
58.933195(5) |
| Ìtòléra ẹ̀lẹ́ktrónì |
[Ar] 4s2 3d7
2, 8, 15, 2 |
| Physical properties |
| Color |
metallic gray |
| Density (near r.t.) |
8.90 g·cm−3 |
| Liquid density at m.p. |
7.75 g·cm−3 |
| Melting point |
1768 K, 1495 °C, 2723 °F |
| Boiling point |
3200 K, 2927 °C, 5301 °F |
| Heat of fusion |
16.06 kJ·mol−1 |
| Heat of vaporization |
377 kJ·mol−1 |
| Molar heat capacity |
24.81 J·mol−1·K−1 |
| Vapor pressure |
| P (Pa) |
1 |
10 |
100 |
1 k |
10 k |
100 k |
| at T (K) |
1790 |
1960 |
2165 |
2423 |
2755 |
3198 |
|
| Atomic properties |
| Oxidation states |
5, 4 , 3, 2, 1 [1], -1
(amphoteric oxide) |
| Electronegativity |
1.88 (Pauling scale) |
Ionization energies
(more) |
1st: 760.4 kJ·mol−1 |
| 2nd: 1648 kJ·mol−1 |
| 3rd: 3232 kJ·mol−1 |
| Atomic radius |
125 pm |
| Covalent radius |
126±3 (low spin), 150±7 (high spin) pm |
| Miscellanea |
| Crystal structure |
hexagonal
|
| Magnetic ordering |
ferromagnetic |
| Electrical resistivity |
(20 °C) 62.4 nΩ·m |
| Thermal conductivity |
100 W·m−1·K−1 |
| Thermal expansion |
(25 °C) 13.0 µm·m−1·K−1 |
| Speed of sound (thin rod) |
(20 °C) 4720 m·s−1 |
| Young's modulus |
209 GPa |
| Shear modulus |
75 GPa |
| Bulk modulus |
180 GPa |
| Poisson ratio |
0.31 |
| Mohs hardness |
5.0 |
| Vickers hardness |
1043 MPa |
| Brinell hardness |
700 MPa |
| CAS registry number |
7440-48-4 |
| Àwọn ísótòpù dídúró jùlọ |
| Main article: Àwọn ísótòpù cobalt |
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· r |
- ↑ Choi, Hyungsoo (2003). "Liquid Cobalt (I) Hydride Complexes as Precursors for Chemical Vapor Deposition". Chemistry of Materials 15: 3121. doi:10.1021/cm030100e.
