Lanthanum (pípè /ˈlænθənəm/) je apilese kemika to ni ami-idamo La ati nomba atomu 57.

Lanthanum, 57La
Lanthanum
Pípè /ˈlænθənəm/ (LAN-thə-nəm)
Ìhànsójúsilvery white
Ìwúwo átọ̀mù Ar, std(La)138.90547(7)[1]
Lanthanum ní orí tábìlì àyè
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 Nihonium Flerovium Moscovium Livermorium Tennessine Oganesson
Y

La

Ac
bariumlanthanumcerium
Nọ́mbà átọ̀mù (Z)57
Ẹgbẹ́group 3
Àyèàyè 6
Àdìpọ̀Àdìpọ̀-f
Ẹ̀ka ẹ́límẹ́ntì  Lanthanide
Ìtò ẹ̀lẹ́ktrọ́nù[Xe] 5d1 6s2
Iye ẹ̀lẹ́ktrọ́nù lórí ìpele kọ̀ọ̀kan2, 8, 18, 18, 9, 2
Àwọn ohun ìní ara
Ìfarahàn at STPsolid
Ìgbà ìyọ́1193 K ​(920 °C, ​1688 °F)
Ígbà ìhó3737 K ​(3464 °C, ​6267 °F)
Kíki (near r.t.)6.162 g/cm3
when liquid (at m.p.)5.94 g/cm3
Heat of fusion6.20 kJ/mol
Heat of 402.1 kJ/mol
Molar heat capacity27.11 J/(mol·K)
 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,[2] +1, +2, +3 Àdàkọ:Infobox element/symbol-to-oxidation-state/comment
ElectronegativityPauling scale: 1.10
Atomic radiusempirical: 187 pm
Covalent radius207±8 pm
Color lines in a spectral range
Color lines in a spectral range
Spectral lines of lanthanum
Other properties
Natural occurrenceprimordial
Crystal structurehexagonal
Hexagonal crystal structure for lanthanum
Speed of sound thin rod2475 m/s (at 20 °C)
Thermal expansion(r.t.) (α, poly) 12.1 µm/(m·K)
Thermal conductivity13.4 W/(m·K)
Electrical resistivity(r.t.) (α, poly) 615 n Ω·m
Magnetic orderingparamagnetic[3]
Young's modulus(α form) 36.6 GPa
Shear modulus(α form) 14.3 GPa
Bulk modulus(α form) 27.9 GPa
Poisson ratio(α form) 0.280
Mohs hardness2.5
Vickers hardness491 MPa
Brinell hardness363 MPa
CAS Number7439-91-0
Main isotopes of lanthanum
Iso­tope Abun­dance Half-life (t1/2) Decay mode Pro­duct
137La syn 60,000 yrs ε 0.600 137Ba
138La 0.09% 1.05×1011yrs ε 1.737 138Ba
β 1.044 138Ce
139La 99.91% 139La is stable with 82 neutrons
Àdàkọ:Category-inline
| references



  1. Meija, Juris; Coplen, Tyler B.; Berglund, Michael; Brand, Willi A.; De Bièvre, Paul; Gröning, Manfred; Holden, Norman E.; Irrgeher, Johanna et al. (2016). "Atomic weights of the elements 2013 (IUPAC Technical Report)". Pure and Applied Chemistry 88 (3): 265–91. doi:10.1515/pac-2015-0305. 
  2. Yttrium and all lanthanides except Ce, Pm, Eu, Tm, Yb 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. 
  3. Magnetic susceptibility of the elements and inorganic compounds, in Handbook of Chemistry and Physics. CRC press. 2000. ISBN 0849304814. http://www-d0.fnal.gov/hardware/cal/lvps_info/engineering/elementmagn.pdf.