57La
Lanthanum
란타넘 · ランタン
Lanthanide
Atomic number57
ElementLa — Lanthanum
Atomic mass138.91
CategoryLanthanide
Group3
Period6
Electron config[Xe] 5d1 6s2
Shells2,8,18,18,9,2
State (RT)Solid
Melting pt920°C
Boiling pt3464°C
Electronegativity1.1
Discovered1839
Main usesCamera lenses, lighter flints
2 · 8 · 18 · 18 · 9 · 2
Group 3
Sc ScandiumY YttriumCe CeriumPr PraseodymiumNd NeodymiumPm PromethiumSm SamariumEu EuropiumGd GadoliniumTb TerbiumDy DysprosiumHo HolmiumEr ErbiumTm ThuliumYb YtterbiumLu LutetiumAc ActiniumTh ThoriumPa ProtactiniumU UraniumNp NeptuniumPu PlutoniumAm AmericiumCm CuriumBk BerkeliumCf CaliforniumEs EinsteiniumFm FermiumMd MendeleviumNo NobeliumLr Lawrencium