Iridium vs Thallium

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PropertyIr IridiumTl Thallium
Atomic number7781
SymbolIrTl
NameIridiumThallium
Categorytransition-metalpost-transition-metal
Standard Atomic Weight192.217 u204.3835 u
Period66
Group913
Blocksp
Phase at STPsolidsolid
Electron configuration[Xe]6s24f145d7[Xe]6s24f145d106p1
Oxidation states[-3, -2, -1, 1, 2, 3, 4, 5, 6, 7, 8, 9][-5, -2, -1, 1, 2, 3]
Electronegativity (Pauling)2.21.62
Electron affinity1.565 eV0.377 eV
Density2.256220e+4 kg/m³1.180000e+4 kg/m³
Melting point2445.85 °C303.85 °C
Boiling point4427.85 °C1472.85 °C
Discovery year18031861