Lanthanum

Lanthanum
57La
Y ↑ La ↓ Ac Tábìlì ìdásìkò barium ← lanthanum → cerium
Ìhànsójú
silvery white
Àwọn ìdámọ́ wíwọ́pọ̀
Orúkọ, àmì-ìdámọ́, nọ́mbà	lanthanum, La, 57
Ẹ̀ka ẹ́límẹ̀nti	lanthanide
Ẹgbẹ́, àsìkò, àdìpò	n/a, 6, f
Ìwúwo átọ́mù	138.90547
Ìtòléra ẹ̀lẹ́ktrónì	[Xe] 5d1 6s2 2, 8, 18, 18, 9, 2
Physical properties
Phase	solid
Density (near r.t.)	6.162 g·cm−3
Liquid density at m.p.	5.94 g·cm−3
Melting point	1193 K, 920 °C, 1688 °F
Boiling point	3737 K, 3464 °C, 6267 °F
Heat of fusion	6.20 kJ·mol−1
Heat of vaporization	402.1 kJ·mol−1
Molar heat capacity	27.11 J·mol−1·K−1
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 states	3, 2 (strongly basic oxide)
Electronegativity	1.10 (Pauling scale)
Ionization energies	1st: 538.1 kJ·mol−1
	2nd: 1067 kJ·mol−1
	3rd: 1850.3 kJ·mol−1
Atomic radius	187 pm
Covalent radius	207±8 pm
Miscellanea
Crystal structure	hexagonal
Magnetic ordering	paramagnetic
Electrical resistivity	(r.t.) (α, poly) 615 nΩ·m
Thermal conductivity	13.4 W·m−1·K−1
Thermal expansion	(r.t.) (α, poly) 12.1 µm/(m·K)
Speed of sound (thin rod)	(20 °C) 2475 m·s−1
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 hardness	2.5
Vickers hardness	491 MPa
Brinell hardness	363 MPa
CAS registry number	7439-91-0
Àwọn ísótòpù dídúró jùlọ
Main article: Àwọn ísótòpù lanthanum
iso NA half-life DM DE (MeV) DP 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

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