Lanthanum vs Thallium

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PropertyLa LanthanumTl Thallium
Atomic number5781
SymbolLaTl
NameLanthanumThallium
Categorylanthanidepost-transition-metal
Standard Atomic Weight138.90547 u204.3835 u
Period66
GroupN/A13
Blocksp
Phase at STPsolidsolid
Electron configuration[Xe]6s25d1[Xe]6s24f145d106p1
Oxidation states[0, 1, 2, 3][-5, -2, -1, 1, 2, 3]
Electronegativity (Pauling)1.11.62
Electron affinity0.47 eV0.377 eV
Density6150 kg/m³1.180000e+4 kg/m³
Melting point917.85 °C303.85 °C
Boiling point3463.85 °C1472.85 °C
Discovery year18391861