General: |
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Name: Lanthanum
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Symbol: La
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Group: Trans. Met.
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Atomic weight: 138.9055
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Density @ 293 K: 6.7 g/cm3
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Atomic volume: 20.73 cm3/mol
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Group: Trans. Met.
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discovered: 1839
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States: |
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state (s, l, g): s
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melting point: 1193.2 K
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boiling point: 3693 K
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Heat of fusion: 6.20 kJ/mol
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Heat of vaporization: 414.0 kJ/mol
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Energies: |
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1st ionization energy: 538.1 kJ/mole
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electronegativity: 1.1
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2nd ionization energy: 1067 kJ/mole
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electron affinity: 50 kJ/mole
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3rd ionization energy: 1850 kJ/mole
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Specific heat: 0.19 J/gK
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heat atomization: 423 kJ/mole atoms
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Oxidation & Electrons: |
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Shells: 2,8,18,18,9,2
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electron configuration: [Xe] 5d1 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: cp: close packed (ABCB)
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color: silvery-white
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uses: lighter flints, CRTs
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toxicity:
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hardness: mohs
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characteristics: soft, malleable
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Reactions: |
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reaction with air: vigorous, w/ht =>La2O3
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reaction with 6M HCl: mild, =>H2, LaCl3
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reaction with 6M HCl: mild, =>H2, LaCl3
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reaction with 15M HNO3: mild, =>La(NO3)3
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reaction with 6M NaOH:
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Other Forms: |
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number of isotopes: 2
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hydride(s): LaH2 LaH3
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oxide(s): La2O3
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chloride(s): LaCl3
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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: 187 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): 117.2 pm
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Conductivity: |
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thermal conductivity: 13.4 J/m-sec-deg
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electrical conductivity: 14.2 1/mohm-cm
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polarizability: 31.1 A^3
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Abundance: |
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source: Monazite(phosphate),bastnaesite
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rel. abund. solar system: -0.351 log
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abundance earth's crust: 1.5 log
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cost, pure: 64 $/100g
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cost, bulk: $/100g
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