General: |
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Name: Holmium
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Symbol: Ho
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Group: Rare Earth, Lanthanides
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Atomic weight: 164.9304
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Density @ 293 K: 8.80 g/cm3
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Atomic volume: 18.7 cm3/mol
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Group: Rare Earth, Lanthanides
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discovered: 1879
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States: |
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state (s, l, g): s
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melting point: 1743.2 K
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boiling point: 2873 K
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Heat of fusion: 12.20 kJ/mol
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Heat of vaporization: 241.0 kJ/mol
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Energies: |
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1st ionization energy: 580.7 kJ/mole
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electronegativity: 1.23
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2nd ionization energy: 1139 kJ/mole
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electron affinity: 50 kJ/mole
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3rd ionization energy: 2204 kJ/mole
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Specific heat: 0.16 J/gK
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heat atomization: 301 kJ/mole atoms
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Oxidation & Electrons: |
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Shells: 2,8,18,29,8,2
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electron configuration: [Xe] 4f11 6s2
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minimum oxidation number: 0
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maximum oxidation number: 3
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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: silvery-white
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uses: alloys
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toxicity:
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hardness: mohs
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characteristics:
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Reactions: |
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reaction with air: vigorous, =>Ho2O3
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reaction with 6M HCl: mild, =>H2, HoCl3
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reaction with 6M HCl: mild, =>H2, HoCl3
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reaction with 15M HNO3: mild, =>Ho(NO3)3
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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): HoH2 HoH3
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oxide(s): Ho2O3
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chloride(s): HoCl3
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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: 176 pm
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ionic radius (1+ ion): pm
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ionic radius (2+ ion): pm
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ionic radius (3+ ion): 104.1 pm
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Conductivity: |
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thermal conductivity: 16.2 J/m-sec-deg
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electrical conductivity: 11.4 1/mohm-cm
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polarizability: 23.6 A^3
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Abundance: |
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source: Monazite(phosphate),bastnaesite
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rel. abund. solar system: -1.051 log
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abundance earth's crust: 0.1 log
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cost, pure: 740 $/100g
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cost, bulk: $/100g
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