Thallium vs Lead

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PropertyTl ThalliumPb Lead
Atomic number8182
SymbolTlPb
NameThalliumLead
Categorypost-transition-metalpost-transition-metal
Standard Atomic Weight204.3835 u207.2 u
Period66
Group1314
Blockpp
Phase at STPsolidsolid
Electron configuration[Xe]6s24f145d106p1[Xe]6s24f145d106p2
Oxidation states[-5, -2, -1, 1, 2, 3][-4, -2, -1, 0, 1, 2, 3, 4]
Electronegativity (Pauling)1.622.33
Electron affinity0.377 eV0.364 eV
Density1.180000e+4 kg/m³1.134200e+4 kg/m³
Melting point303.85 °C327.46 °C
Boiling point1472.85 °C1748.85 °C
Discovery year18612021