Cobalt

Cobalt (Co)

Light grey transition element. Some meteorites contain small amounts of metallic cobalt. Generally alloyed for use. Mammals require small amounts of cobalt salts. Cobalt-60, an artificially produced radioactive isotope of Cobalt is an important radioactive tracer and cancer-treatment agent. Discovered by G. Brandt in 1737.
Atomic Number27
Atomic Weight58.933194
Mass Number59
Group9
Period4
Blockd
Protons27 p+
Neutrons32 n0
Electrons27 e-
Kobalt electrolytic and 1cm3 cube.jpg Animated Bohr Model of Co (Cobalt) Enhanced Bohr Model of Co (Cobalt) Bohr Model: Co (Cobalt) Orbital Diagram of Co (Cobalt)

Properties

Atomic Radius
135 pm
Molar Volume
Covalent Radius
111 pm
Metallic Radius
116 pm
Ionic Radius
58 pm
Crystal Radius
72 pm
Van der Waals Radius
200 pm
Density
8.86 g/cm³
Energy
Proton Affinity
742.7 kJ/mol
Electron Affinity
0.66225646 eV/particle
Ionization Energy
7.88101 eV/particle
Heat of Vaporization
389.1 kJ/mol
Heat of Fusion
15.48 kJ/mol
Heat of Formation
426.7 kJ/mol
Electrons
Electron Shells2, 8, 15, 2
Valence Electrons4
Electron Configuration[Ar] 3d7 4s2
Oxidation States-3, -1, 0, 1, 2, 3, 4, 5
Electronegativity
1.88
Electrophilicity
1.2638504937543713 eV/particle
Phases
PhaseSolid
Gas Phase
Boiling Point
3,200.15 K
Melting Point
1,768.15 K
Critical Pressure
Critical Temperature
Triple Point
Visual
Color
Gray
Appearancehard lustrous gray metal
Refractive Index
Thermodynamic Properties
Thermal Conductivity
Thermal Expansion
0.000013 1/K
Molar Heat Capacity
24.81 J/(mol K)
Specific Heat Capacity
0.421 J/(g⋅K)
Heat Capacity Ratio (Adiabatic Index)
Electrical Properties
TypeConductor
Electrical Conductivity
17 MS/m
Electrical Resistivity
0.00000006000000000002 m Ω
Superconducting Point
Magnetism
Typeferromagnetic
Magnetic Susceptibility (Mass)
Magnetic Susceptibility (Molar)
Magnetic Susceptibility (Volume)
Magnetic Ordering
Curie Point
1,394 K
Neel Point
Structure
Crystal StructureSimple Hexagonal (HEX)
Lattice Constant
2.51 Å
Lattice Anglesπ/2, π/2, 2 π/3
Mechanical Properties
Hardness
5 MPa
Bulk Modulus
180 GPa
Shear Modulus
75 GPa
Young Modulus
209 GPa
Poisson Ratio
0.31
Speed of Sound
4,720 m/s
Classification
CategoryTransition metals, Transition metals
CAS GroupVIIIA
IUPAC GroupVIII
Glawe Number70
Mendeleev Number63
Pettifor Number64
Geochemical Classfirst series transition metal
Goldschmidt Classsiderophile
Other
Gas Basicity
719.8 kJ/mol
Dipole Polarizability
55 ± 4 a₀
C6 Dispersion Coefficient
408 a₀
Allotropes
Neutron Cross Section
37.2
Neutron Mass Absorption
0.021
Quantum Numbers4F9/2
Space Group194 (P63/mmc)

Isotopes of Cobalt

Stable Isotopes1
Unstable Isotopes31
Radioactive Isotopes28

47Co

Abundance
Relative Atomic Mass
47.011401 ± 0.000644 Da
Mass Number47
G-Factor
Half Life
Spin7/2
Quadrupole Moment
Discovery Year
Parity-

47Co Decay Modes
Decay ModeIntensity
p (proton emission)%

48Co

Abundance
Relative Atomic Mass
48.001857 ± 0.000537 Da
Mass Number48
G-Factor
Half Life
Spin6
Quadrupole Moment
Discovery Year
Parity+

48Co Decay Modes
Decay ModeIntensity
p (proton emission)%

49Co

Abundance
Relative Atomic Mass
48.989501 ± 0.000537 Da
Mass Number49
G-Factor
Half Life
Spin7/2
Quadrupole Moment
Discovery Year
Parity-

49Co Decay Modes
Decay ModeIntensity
p (proton emission)%

50Co

AbundanceRadioactive ☢️
Relative Atomic Mass
49.981117 ± 0.000135 Da
Mass Number50
G-Factor
Half Life
38.8 ± 0.2 ms
Spin6
Quadrupole Moment
Discovery Year1987
Parity+

50Co Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%
β+ p (β+-delayed proton emission)70.5%
2p (2-proton emission)%

51Co

AbundanceRadioactive ☢️
Relative Atomic Mass
50.970647 ± 0.000052 Da
Mass Number51
G-Factor
Half Life
68.8 ± 1.9 ms
Spin7/2
Quadrupole Moment
Discovery Year1987
Parity-

51Co Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%
β+ p (β+-delayed proton emission)3.8%

52Co

AbundanceRadioactive ☢️
Relative Atomic Mass
51.963130224 ± 0.000005669 Da
Mass Number52
G-Factor
Half Life
111.7 ± 2.1 ms
Spin6
Quadrupole Moment
Discovery Year1987
Parity+

52Co Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%
β+ p (β+-delayed proton emission)%

53Co

AbundanceRadioactive ☢️
Relative Atomic Mass
52.954203278 ± 0.000001854 Da
Mass Number53
G-Factor
Half Life
244.6 ± 2.8 ms
Spin7/2
Quadrupole Moment
Discovery Year1970
Parity-

53Co Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

54Co

AbundanceRadioactive ☢️
Relative Atomic Mass
53.948459075 ± 0.00000038 Da
Mass Number54
G-Factor
0
Half Life
193.27 ± 0.06 ms
Spin0
Quadrupole Moment
0
Discovery Year1952
Parity+

54Co Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

55Co

AbundanceRadioactive ☢️
Relative Atomic Mass
54.941996416 ± 0.000000434 Da
Mass Number55
G-Factor
1.3777142857143 ± 0.00085714285714286
Half Life
17.53 ± 0.03 h
Spin7/2
Quadrupole Moment
Discovery Year1938
Parity-

55Co Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

56Co

AbundanceRadioactive ☢️
Relative Atomic Mass
55.939838032 ± 0.00000051 Da
Mass Number56
G-Factor
0.9625 ± 0.0025
Half Life
77.236 ± 0.026 d
Spin4
Quadrupole Moment
0.25 ± 0.09
Discovery Year1941
Parity+

56Co Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

57Co

AbundanceRadioactive ☢️
Relative Atomic Mass
56.936289819 ± 0.000000553 Da
Mass Number57
G-Factor
1.3485714285714 ± 0.0028571428571429
Half Life
271.811 ± 0.032 d
Spin7/2
Quadrupole Moment
0.54 ± 0.1
Discovery Year1941
Parity-

57Co Decay Modes
Decay ModeIntensity
ϵ (electron capture)100%

58Co

AbundanceRadioactive ☢️
Relative Atomic Mass
57.935751292 ± 0.000001237 Da
Mass Number58
G-Factor
2.022 ± 0.004
Half Life
70.844 ± 0.02 d
Spin2
Quadrupole Moment
0.23 ± 0.03
Discovery Year1941
Parity+

58Co Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%
e+ (positron emission)14.79%
ϵ (electron capture)85.21%

59Co

Abundance
100
Relative Atomic Mass
58.933193524 ± 0.000000426 Da
Mass Number59
G-Factor
Half Life
Spin7/2
Quadrupole Moment
0.42 ± 0.03
Discovery Year1923
Parity-

60Co

AbundanceRadioactive ☢️
Relative Atomic Mass
59.933815536 ± 0.000000433 Da
Mass Number60
G-Factor
0.7598 ± 0.0016
Half Life
5.2714 ± 0.0006 y
Spin5
Quadrupole Moment
0.46 ± 0.06
Discovery Year1941
Parity+

60Co Decay Modes
Decay ModeIntensity
β (β decay)100%

61Co

AbundanceRadioactive ☢️
Relative Atomic Mass
60.932476031 ± 0.000000901 Da
Mass Number61
G-Factor
Half Life
1.649 ± 0.005 h
Spin7/2
Quadrupole Moment
Discovery Year1947
Parity-

61Co Decay Modes
Decay ModeIntensity
β (β decay)100%

62Co

AbundanceRadioactive ☢️
Relative Atomic Mass
61.934058198 ± 0.00001994 Da
Mass Number62
G-Factor
Half Life
1.54 ± 0.1 m
Spin2
Quadrupole Moment
Discovery Year1949
Parity

62Co Decay Modes
Decay ModeIntensity
β (β decay)100%

63Co

AbundanceRadioactive ☢️
Relative Atomic Mass
62.93359963 ± 0.000019941 Da
Mass Number63
G-Factor
Half Life
26.9 ± 0.4 s
Spin7/2
Quadrupole Moment
Discovery Year1960
Parity-

63Co Decay Modes
Decay ModeIntensity
β (β decay)100%

64Co

AbundanceRadioactive ☢️
Relative Atomic Mass
63.935810176 ± 0.000021476 Da
Mass Number64
G-Factor
Half Life
300 ± 30 ms
Spin1
Quadrupole Moment
Discovery Year1969
Parity+

64Co Decay Modes
Decay ModeIntensity
β (β decay)100%

65Co

AbundanceRadioactive ☢️
Relative Atomic Mass
64.936462071 ± 0.000002235 Da
Mass Number65
G-Factor
Half Life
1.16 ± 0.03 s
Spin7/2
Quadrupole Moment
Discovery Year1978
Parity

65Co Decay Modes
Decay ModeIntensity
β (β decay)100%

66Co

AbundanceRadioactive ☢️
Relative Atomic Mass
65.939442943 ± 0.000015 Da
Mass Number66
G-Factor
Half Life
194 ± 17 ms
Spin1
Quadrupole Moment
Discovery Year1985
Parity+

66Co Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)%

67Co

AbundanceRadioactive ☢️
Relative Atomic Mass
66.940609625 ± 0.000006917 Da
Mass Number67
G-Factor
Half Life
329 ± 28 ms
Spin7/2
Quadrupole Moment
Discovery Year1985
Parity-

67Co Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)%

68Co

AbundanceRadioactive ☢️
Relative Atomic Mass
67.944559401 ± 0.000004142 Da
Mass Number68
G-Factor
Half Life
200 ± 20 ms
Spin7
Quadrupole Moment
Discovery Year1985
Parity-

68Co Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)%

69Co

AbundanceRadioactive ☢️
Relative Atomic Mass
68.945909 ± 0.000092 Da
Mass Number69
G-Factor
Half Life
180 ± 20 ms
Spin7/2
Quadrupole Moment
Discovery Year1985
Parity-

69Co Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)%

70Co

AbundanceRadioactive ☢️
Relative Atomic Mass
69.9500534 ± 0.0000118 Da
Mass Number70
G-Factor
Half Life
508 ± 7 ms
Spin1
Quadrupole Moment
Discovery Year1998
Parity+

70Co Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)%
2n (2-neutron emission)%

71Co

AbundanceRadioactive ☢️
Relative Atomic Mass
70.952366923 ± 0.00049923 Da
Mass Number71
G-Factor
Half Life
80 ± 3 ms
Spin7/2
Quadrupole Moment
Discovery Year1992
Parity-

71Co Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)3%

72Co

AbundanceRadioactive ☢️
Relative Atomic Mass
71.956736 ± 0.000322 Da
Mass Number72
G-Factor
Half Life
51.5 ± 0.3 ms
Spin6
Quadrupole Moment
Discovery Year1992
Parity-

72Co Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)4%
2n (2-neutron emission)%

73Co

AbundanceRadioactive ☢️
Relative Atomic Mass
72.959238 ± 0.000322 Da
Mass Number73
G-Factor
Half Life
42 ± 0.8 ms
Spin7/2
Quadrupole Moment
Discovery Year1995
Parity-

73Co Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)6%
2n (2-neutron emission)%

74Co

AbundanceRadioactive ☢️
Relative Atomic Mass
73.963993 ± 0.000429 Da
Mass Number74
G-Factor
Half Life
31.3 ± 1.3 ms
Spin7
Quadrupole Moment
Discovery Year1995
Parity-

74Co Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)18%
2n (2-neutron emission)%

75Co

AbundanceRadioactive ☢️
Relative Atomic Mass
74.967192 ± 0.000429 Da
Mass Number75
G-Factor
Half Life
26.5 ± 1.2 ms
Spin7/2
Quadrupole Moment
Discovery Year1995
Parity-

75Co Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)16%
2n (2-neutron emission)%

76Co

AbundanceRadioactive ☢️
Relative Atomic Mass
75.972453 ± 0.000537 Da
Mass Number76
G-Factor
Half Life
23 ± 6 ms
Spin8
Quadrupole Moment
Discovery Year2010
Parity-

76Co Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)%
2n (2-neutron emission)%

77Co

AbundanceRadioactive ☢️
Relative Atomic Mass
76.976479 ± 0.000644 Da
Mass Number77
G-Factor
Half Life
15 ± 6 ms
Spin7/2
Quadrupole Moment
Discovery Year2014
Parity-

77Co Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)%
2n (2-neutron emission)%
3n (3-neutron emission)%

78Co

AbundanceRadioactive ☢️
Relative Atomic Mass
77.983553 ± 0.000751 Da
Mass Number78
G-Factor
Half Life
Spin
Quadrupole Moment
Discovery Year2017
Parity

78Co Decay Modes
Decay ModeIntensity
β (β decay)%

History

Cobalt compounds have been used for centuries to impart a rich blue color to glass, glazes and ceramics. The element was first isolated by Swedish chemist George Brandt in 1735. He showed it was the presence of the element cobalt that caused the blue color in glass, not bismuth as previously thought. From the German word Kobald, goblin or evil spirit; also from the Greek cobalos, mine

DiscoverersGeorge Brandt
Discovery LocationSweden
Discovery Year1739
Etymology (Name Origin)German: kobold (goblin).
PronunciationKO-bolt (English)
Cobalt and its compounds are considered to be slightly toxic
Supplemental colbalt is essential in sheep's diets to improve the wools quality

Uses

Cobalt is used in the preparation of magnetic, wear-resistant and high-strength alloys. Cobalt is widely used in batteries and in electroplating. Radioactive 60Co is used in the treatment of cancer. A solution of the chloride is used as a sympathetic ink. Used in many hard alloys; for magnets, ceramics and special glasses. Remains hard up to 982°C. Radioactive cobalt-60 is used in cancer therapy.

Sources

Occurs in compounds with arsenic, oxygen and sulfur as in cobaltine (CoAsS) and linneite (Co3S4). Pure cobalt is obtained as a byproduct of refining nickel, copper and iron.

Abundance
Abundance in Earth's crust
Abundance in Oceans
0.00002 mg/L
Abundance in Human Body
0.000002 %
Abundance in Meteor
0.059 %
Abundance in Sun
0.0004 %
Abundance in Universe
0.0003 %

Nuclear Screening Constants

1s0.6332
2p3.9076
2s7.595
3d15.1446
3p13.5654
3s12.6777
4s21.4236