Gadolinium vs Astatine

PropertyGd GadoliniumAt Astatine
Atomic number6485
SymbolGdAt
NameGadoliniumAstatine
Categorylanthanidehalogen
Standard Atomic Weight157.25 u210 u
Period66
GroupN/A17
Blocksp
Phase at STPsolidsolid
Electron configuration[Xe]6s24f75d1[Xe]6s24f145d106p5
Oxidation states[0, 1, 2, 3][-1, 1, 3, 5, 7]
Electronegativity (Pauling)1.22.2
Electron affinity0.132 eV2.391 eV
Density7900 kg/m³7000 kg/m³
Melting point1312.85 °C301.85 °C
Boiling point3272.85 °C-273.15 °C
Discovery year18861940