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 General | States | Energies | Oxidation & Electrons | Appearance & Characteristics | Reactions | Other Forms Radius | Conductivity | Abundance


Name: Lanthanum Symbol: La
Group: Trans. Met. Atomic weight: 138.9055
Density @ 293 K: 6.7 g/cm3 Atomic volume: 20.73 cm3/mol
Group: Trans. Met. discovered: 1839


state (s, l, g): s
melting point: 1193.2 K boiling point: 3693 K
Heat of fusion: 6.20 kJ/mol Heat of vaporization: 414.0 kJ/mol


1st ionization energy: 538.1 kJ/mole
electronegativity: 1.1 2nd ionization energy: 1067 kJ/mole
electron affinity: 50 kJ/mole 3rd ionization energy: 1850 kJ/mole
Specific heat: 0.19 J/gK heat atomization: 423 kJ/mole atoms

Oxidation & Electrons:

Shells: 2,8,18,18,9,2 electron configuration: [Xe] 5d1 6s2
minimum oxidation number: 0 maximum oxidation number: 3
min. common oxidation no.: 0 max. common oxidation no.: 3

Appearance & Characteristics:

structure: cp: close packed (ABCB) color: silvery-white
uses: lighter flints, CRTs toxicity:
hardness: mohs characteristics: soft, malleable


reaction with air: vigorous, w/ht =>La2O3
reaction with 6M HCl: mild, =>H2, LaCl3 reaction with 6M HCl: mild, =>H2, LaCl3
reaction with 15M HNO3: mild, =>La(NO3)3 reaction with 6M NaOH:

Other Forms:

number of isotopes: 2 hydride(s): LaH2 LaH3
oxide(s): La2O3 chloride(s): LaCl3


ionic radius (2- ion): pm ionic radius (1- ion): pm
atomic radius: 187 pm ionic radius (1+ ion): pm
ionic radius (2+ ion): pm ionic radius (3+ ion): 117.2 pm


thermal conductivity: 13.4 J/m-sec-deg
electrical conductivity: 14.2 1/mohm-cm polarizability: 31.1 A^3


source: Monazite(phosphate),bastnaesite
rel. abund. solar system: -0.351 log abundance earth's crust: 1.5 log
cost, pure: 64 $/100g cost, bulk: $/100g