మూస:లాంథనం మూలకము

లాంథనం, 00La
లాంథనం
Pronunciation/ˈlænθənəm/ (LAN-thə-nəm)
Appearancesilvery white
Standard atomic weight Ar°(La)
లాంథనం in the periodic table
Hydrogen Helium
Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon
Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon
Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton
Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver Cadmium Indium Tin Antimony Tellurium Iodine Xenon
Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury (element) Thallium Lead Bismuth Polonium Astatine Radon
Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Ununtrium Flerovium Ununpentium Livermorium Ununseptium Ununoctium


La

Ac
బేరియంలాంథనంసీరియం
Groupమూస:Infobox element/symbol-to-group/format
Periodperiod 6
Block  f-block
Electron configuration[Xe] 5d1 6s2
Electrons per shell2, 8, 18, 18, 9, 2
Physical properties
Phase at STPsolid
Melting point1193 K ​(920 °C, ​1688 °F)
Boiling point3737 K ​(3464 °C, ​6267 °F)
Density (near r.t.)6.162 g/cm3
when liquid (at m.p.)5.94 g/cm3
Heat of fusion6.20 kJ/mol
Heat of vaporization400 kJ/mol
Molar heat capacity27.11 J/(mol·K)
Vapor pressure (extrapolated)
P (Pa) 1 10 100 1 k 10 k 100 k
at T (K) 2005 2208 2458 2772 3178 3726
Atomic properties
Oxidation states0,[3] +1,[4] +2, +3 (a strongly basic oxide)
ElectronegativityPauling scale: 1.10
Ionization energies
  • 1st: 538.1 kJ/mol
  • 2nd: 1067 kJ/mol
  • 3rd: 1850.3 kJ/mol
Atomic radiusempirical: 187 pm
Covalent radius207±8 pm
Color lines in a spectral range
Spectral lines of లాంథనం
Other properties
Natural occurrenceprimordial
Crystal structurehexagonal
Hexagonal crystal structure for లాంథనం
Speed of sound thin rod2475 m/s (at 20 °C)
Thermal expansionα, poly: 12.1 µm/(m⋅K) (at r.t.)
Thermal conductivity13.4 W/(m⋅K)
Electrical resistivityα, poly: 615 nΩ⋅m (at r.t.)
Magnetic orderingparamagnetic[5]
Young's modulusα form: 36.6 GPa
Shear modulusα form: 14.3 GPa
Bulk modulusα form: 27.9 GPa
Poisson ratioα form: 0.280
Mohs hardness2.5
Vickers hardness491 MPa
Brinell hardness363 MPa
CAS Number7439-91-0
History
DiscoveryCarl Gustaf Mosander (1838)
Isotopes of లాంథనం
Template:infobox లాంథనం isotopes does not exist
 Category: లాంథనం
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References

  1. "Standard Atomic Weights: Lanthanum". CIAAW. 2005.
  2. Prohaska, Thomas; Irrgeher, Johanna; Benefield, Jacqueline; et al. (2022-05-04). "Standard atomic weights of the elements 2021 (IUPAC Technical Report)". Pure and Applied Chemistry (in ఇంగ్లీష్). doi:10.1515/pac-2019-0603. ISSN 1365-3075.
  3. Yttrium and all lanthanides except Ce and Pm have been observed in the oxidation state 0 in bis(1,3,5-tri-t-butylbenzene) complexes, see Cloke, F. Geoffrey N. (1993). "Zero Oxidation State Compounds of Scandium, Yttrium, and the Lanthanides". Chem. Soc. Rev. 22: 17–24. doi:10.1039/CS9932200017. and Arnold, Polly L.; Petrukhina, Marina A.; Bochenkov, Vladimir E.; Shabatina, Tatyana I.; Zagorskii, Vyacheslav V.; Cloke (2003-12-15). "Arene complexation of Sm, Eu, Tm and Yb atoms: a variable temperature spectroscopic investigation". Journal of Organometallic Chemistry. 688 (1–2): 49–55. doi:10.1016/j.jorganchem.2003.08.028.
  4. La(I), Pr(I), Tb(I), Tm(I), and Yb(I) have been observed in MB8 clusters; see Li, Wan-Lu; Chen, Teng-Teng; Chen, Wei-Jia; Li, Jun; Wang, Lai-Sheng (2021). "Monovalent lanthanide(I) in borozene complexes". Nature Communications. 12 (1): 6467. doi:10.1038/s41467-021-26785-9. PMC 8578558. PMID 34753931.
  5. Magnetic susceptibility of the elements and inorganic compounds, in Handbook of Chemistry and Physics (PDF). CRC press. 2000. ISBN 0849304814.