Kobalt

Cobalt, ₂₇Co
General properties
Pangucapan	i/ˈkoʊbɒlt/
Wujud	hard lustrous bluish gray metal
Bobot atom standar (Ar, standard)	58.933194(4)
Cobalt in the periodic table
	iron ← cobalt → nickel
Atomic number (Z)	27
Group	group 9
Period	period 4
Element category	transition metal
Blok	d-block
Konfigurasi èlèktron	[Ar] 3d7 4s2
Electrons per shell	2, 8, 15, 2
Sipat angga
Phase at STP	solid
Melting point	1768 K (1495 °C, 2723 °F)
Boiling point	3200 K (2927 °C, 5301 °F)
Density (near r.t.)	8.90 g/cm3
when liquid (at m.p.)	8.86 g/cm3
Heat of fusion	16.06 kJ/mol
Heat of vaporization	377 kJ/mol
Molar heat capacity	24.81 J/(mol·K)
Atomic properties
Oxidation states	−3, −1, +1, +2, +3, +4, +5 (an amphoteric oxide)
Electronegativity	Pauling scale: 1.88
Ionization energies	1st: 760.4 kJ/mol ; 2nd: 1648 kJ/mol ; 3rd: 3232 kJ/mol ; (more) ;
Atomic radius	empirical: 125 pm
Covalent radius	Low spin: 126±3 pm; High spin: 150±7 pm
	Spectral lines
	Spectral lines
Miscellanea
Crystal structure	hexagonal close-packed (hcp)
Speed of sound thin rod	4720 m/s (at 20 °C)
Thermal expansion	13.0 µm/(m·K) (at 25 °C)
Thermal conductivity	100 W/(m·K)
Electrical resistivity	62.4 nΩ·m (at 20 °C)
Magnetic ordering	ferromagnetic
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	470–3000 MPa
CAS Number	7440-48-4
History
Discovery and first isolation	Georg Brandt (1735)
Main isotopes of cobalt
	deleng; rembug; besut; \| references \| in Wikidata

Kobalt iku sawijining anasir kimiah kanthi cihna Co lan nomer atom 27. Kaya nikel, kobalt ditemokaké ing Bumi kanthi bentuké campuran, sing sumber asalé saka mètèorit wesi. sipat iku atos, kemeling, lan wernané klawu wesi.

Sunyata Rikat General properties, Pangucapan ...

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Kobalt

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