Praseodymium vs Thallium

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PropertyPr PraseodymiumTl Thallium
Atomic number5981
SymbolPrTl
NamePraseodymiumThallium
Categorylanthanidepost-transition-metal
Standard Atomic Weight140.90766 u204.3835 u
Period66
GroupN/A13
Blocksp
Phase at STPsolidsolid
Electron configuration[Xe]6s24f3[Xe]6s24f145d106p1
Oxidation states[0, 1, 2, 3, 4, 5][-5, -2, -1, 1, 2, 3]
Electronegativity (Pauling)1.131.62
Electron affinity0.962 eV0.377 eV
Density6770 kg/m³1.180000e+4 kg/m³
Melting point930.85 °C303.85 °C
Boiling point3519.85 °C1472.85 °C
Discovery year18851861