Element Cobalt - Co

Comprehensive data on the chemical element Cobalt is provided on this page; including scores of properties, element names in many languages, most known nuclides of Cobalt. Common chemical compounds are also provided for many elements. In addition technical terms are linked to their definitions and the menu contains links to related articles that are a great aid in one"s studies.

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Cobalt Menu

Cobalt Page OneOverview of CobaltCobalt"s Name in Other LanguagesAtomic Structure of CobaltChemical Properties of CobaltPhysical Properties of CobaltRegulatory / HealthWho/When/Where/HowCobalt Page TwoNuclides / IsotopesPotential Parent NuclidesCobalt Page ThreeCommon Chemical Compounds of Cobalt

Overview of Cobalt

Atomic Number: 27Group: 9Period: 4Series: Transition Metals

Cobalt"s Name in Other Languages

Latin: CobaltumCzech: KobaltCroatian: KobaltFrench: CobaltGerman: Kobalt - rItalian: CobaltoNorwegian: KoboltPortuguese: CobaltoRussian: КобальтSpanish: CobaltoSwedish: KoboltAtomic Structure of CobaltAtomic Radius: 1.67ÅAtomic Volume: 6.7cm3/molCovalent Radius: 1.16ÅCross Section (Thermal Neutron Capture)σa/barns: 37.2Crystal Structure: Hexagonal
Electron Configuration:1s2 2s2p6 3s2p6d7 4s2Electrons per Energy Level: 2,8,15,2Shell Model
Ionic Radius:
0.745ÅFilling Orbital: 3d7Number of Electrons (with no charge): 27Number of Neutrons (most common/stable nuclide): 32Number of Protons: 27Oxidation States: 2,3Valence Electrons: 3d7 4s2

Chemical Properties of Cobalt

Electrochemical Equivalent: 1.0994g/amp-hrElectron Work Function: 5eVElectronegativity: 1.88 (Pauling); 1.7 (Allrod Rochow)Heat of Fusion: 16.19kJ/molIncompatibilities:Strong oxidizers, ammonium nitrateIonization PotentialFirst: 7.86Second: 17.06Third: 33.5Valence Electron Potential (-eV): 38.7

Physical Properties of Cobalt

Atomic Mass Average: 58.9332Boiling Point: 3143K 2870°C 5198°FCoefficient of lineal thermal expansion/K-1: 13.36E-6ConductivityElectrical: 0.172 106/cm ΩThermal: 1 W/cmKDensity: 8.9g/cc
300KDescription:Tough silver-white transition metal.Elastic Modulus:Bulk: 181.5/GPaRigidity: 82/GPaYoungs: 211/GPaEnthalpy of Atomization: 26.8 kJ/mole
25°CEnthalpy of Fusion: 15.23 kJ/moleEnthalpy of Vaporization: 382.4 kJ/moleFlammablity Class: Non-combustible solid (except as dust)Freezing Point: see melting pointHardness ScaleBrinell: 700 MN m-2Mohs: 5Vickers: 1043 MN m-2Heat of Vaporization: 376.5kJ/molMelting Point: 1768K 1495°C 2723°FMolar Volume: 6.61 cm3/moleOptical Reflectivity: 67%Physical State (at 20°C & 1atm): SolidSpecific Heat: 0.42J/gKVapor Pressure = 175Pa

Regulatory / Health

CAS Number7440-48-4RTECS: GF8750000OSHA Permissible Exposure Limit (PEL)TWA: 0.1 mg/m3OSHA PEL Vacated 1989TWA: 0.05 mg/m3NIOSH Recommended Exposure Limit (REL)TWA: 0.05 mg/m3IDLH: 20 mg/m3 Routes of Exposure: Inhalation; Ingestion; Skin and/or eye contactTarget Organs: Skin, respiratory systemLevels In Humans:Note: this data represents naturally occuring levels of elements in the typical human, it DOES NOT represent recommended daily allowances.Blood/mg dm-3: 0.0002-0.04Bone/p.p.m: 0.01-0.04Liver/p.p.m: 0.06-1.1Muscle/p.p.m: 0.028-0.65Daily Dietary Intake: 0.005-1.8 mgTotal Mass In Avg. 70kg human: 3 mg

Who / Where / When / How

Discoverer: George BrandtDiscovery Location: Stockholm SwedenDiscovery Year: 1735Name Origin: German: kobalt or kobold (evil spirit); Greek: cobalos (mines).Abundance of Cobalt:Earth"s Crust/p.p.m.: 20Seawater/p.p.m.: Atlantic Suface: N/AAtlantic Deep: N/APacific Surface: 0.0000069Pacific Deep: 0.0000011Atmosphere/p.p.m.: N/ASun (Relative to H=1E12): 79400Sources of Cobalt:Occurs in compounds with arsenic, oxygen and sulfur as in cobaltine (CoAsS) and linneite (Co3S4). Annual world production is around 17,000 tons. Primary mining areas are in Zaire, Morocco, Sweden and Canada.Uses of Cobalt:Used in many hard alloys; for magnets, ceramics and special glasses. Also used in permanent magnets, razor blades and catalitic converters. Cobalt-60 is used in cancer therapy.Additional Notes:

Cobalt Menu

Cobalt Page OneOverview of CobaltCobalt"s Name in Other LanguagesAtomic Structure of CobaltChemical Properties of CobaltPhysical Properties of CobaltRegulatory / HealthWho/When/Where/HowCobalt Page TwoNuclides / IsotopesPotential Parent NuclidesCobalt Page ThreeCommon Chemical Compounds of Cobalt


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