General: |
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Name: Hafnium
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Symbol: Hf
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Group: Trans. Met.
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Atomic weight: 178.49
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Density @ 293 K: 13.2 g/cm3
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Atomic volume: 13.6 cm3/mol
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Group: Trans. Met.
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discovered: 1923
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States: |
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state (s, l, g): s
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melting point: 2495.2 K
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boiling point: 4723 K
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Heat of fusion: 24.060 kJ/mol
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Heat of vaporization: 575.0 kJ/mol
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Energies: |
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1st ionization energy: 680 kJ/mole
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electronegativity: 1.3
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2nd ionization energy: 1440 kJ/mole
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electron affinity: 0 kJ/mole
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3rd ionization energy: 2250 kJ/mole
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Specific heat: 0.14 J/gK
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heat atomization: 619 kJ/mole atoms
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Oxidation & Electrons: |
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Shells: 2,8,18,32,10,2
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electron configuration: [Xe] 4f14 5d2 6s2
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minimum oxidation number: 0
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maximum oxidation number: 4
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min. common oxidation no.: 0
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max. common oxidation no.: 4
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Appearance & Characteristics: |
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structure: hcp: hexagonal close pkd
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color: silvery
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uses: nuclear control rods
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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, =>HfO2
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reaction with 6M HCl: none
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reaction with 6M HCl: none
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reaction with 15M HNO3: passivated
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reaction with 6M NaOH: none
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Other Forms: |
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number of isotopes: 6
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hydride(s): HfH2
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oxide(s): HfO2
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chloride(s): HfCl3 HfCl4
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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: 159 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): pm
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Conductivity: |
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thermal conductivity: 23.2 J/m-sec-deg
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electrical conductivity: 28.49 1/mohm-cm
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polarizability: 16.2 A^3
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Abundance: |
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source: Zircon (silicate)
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rel. abund. solar system: -0.812 log
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abundance earth's crust: 0.4 log
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cost, pure: 120 $/100g
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cost, bulk: $/100g
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