Template:Infobox cobalt

From Wikipedia, the free encyclopedia
Jump to: navigation, search
ironcobaltnickel
-

Co

Rh
Appearance
hard lustrous gray metal
General properties
Name, symbol, number cobalt, Co, 27
Pronunciation /ˈkbɒlt/ koh-bolt[1]
Element category transition metal
Group, period, block 94, d
Standard atomic weight 58.933195(5)
Electron configuration [Ar] 4s2 3d7
Electrons per shell 2, 8, 15, 2 (Image)
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[2]
(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
Most stable isotopes
Main article: Isotopes of cobalt
iso NA half-life DM DE (MeV) DP
56Co syn 77.27 d ε 4.566 56Fe
57Co syn 271.79 d ε 0.836 57Fe
58Co syn 70.86 d ε 2.307 58Fe
59Co 100% 59Co is stable with 32 neutrons
60Co syn 5.2714 years β, γ, γ 2.824 60Ni
· r

References

  1. ^ Oxford English Dictionary, 2nd Edition 1989.
  2. ^ Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Oxford: Butterworth-Heinemann. pp. 1117–1119. ISBN 0080379419. 
Personal tools
Namespaces
Variants
Actions
Navigation
Interaction
Toolbox
Languages