General: |
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Name: Cobalt
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Symbol: Co
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Group: Trans. Met.
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Atomic weight: 58.9332
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Density @ 293 K: 8.90 g/cm3
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Atomic volume: 6.7 cm3/mol
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Group: Trans. Met.
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discovered: 1737
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States: |
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state (s, l, g): s
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melting point: 1768.2 K
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boiling point: 3373 K
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Heat of fusion: 16.190 kJ/mol
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Heat of vaporization: 376.50 kJ/mol
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Energies: |
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1st ionization energy: 758.4 kJ/mole
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electronegativity: 1.88
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2nd ionization energy: 1646 kJ/mole
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electron affinity: 63.8 kJ/mole
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3rd ionization energy: 3232.2 kJ/mole
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Specific heat: 0.42 J/gK
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heat atomization: 425 kJ/mole atoms
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Oxidation & Electrons: |
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Shells: 2,8,15,2
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electron configuration: [Ar] 3d7 4s2
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minimum oxidation number: -1
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maximum oxidation number: 5
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min. common oxidation no.: 0
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max. common oxidation no.: 3
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Appearance & Characteristics: |
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structure: hcp: hexagonal close pkd
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color: bluish-white
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uses: magnets, Co glass (blue)
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toxicity:
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hardness: mohs
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characteristics: hard
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Reactions: |
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reaction with air: mild, w/ht =>Co3O4
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reaction with 6M HCl: mild, =>H2, CoCl2
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reaction with 6M HCl: mild, =>H2, CoCl2
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reaction with 15M HNO3: vigorous, =>Co(NO3)2, NOx
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reaction with 6M NaOH:
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Other Forms: |
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number of isotopes: 1
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hydride(s): none
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oxide(s): CoO Co3O4
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chloride(s): CoCl2
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Radius: |
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ionic radius (2- ion): pm
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ionic radius (1- ion): pm
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atomic radius: 125 pm
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ionic radius (1+ ion): pm
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ionic radius (2+ ion): 83.8 pm
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ionic radius (3+ ion): 71.8 pm
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Conductivity: |
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thermal conductivity: 100 J/m-sec-deg
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electrical conductivity: 160.256 1/mohm-cm
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polarizability: 7.5 A^3
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Abundance: |
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source: Co sulfides & arsenides
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rel. abund. solar system: 3.352 log
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abundance earth's crust: 1.4 log
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cost, pure: 21 $/100g
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cost, bulk: $/100g
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