Zirconium vs Astatine

PropertyZr ZirconiumAt Astatine
Atomic number4085
SymbolZrAt
NameZirconiumAstatine
Categorytransition-metalhalogen
Standard Atomic Weight91.224 u210 u
Period56
Group417
Blocksp
Phase at STPsolidsolid
Electron configuration[Kr]5s24d2[Xe]6s24f145d106p5
Oxidation states[1, 2, 3, 4][-1, 1, 3, 5, 7]
Electronegativity (Pauling)1.332.2
Electron affinity0.426 eV2.391 eV
Density6520 kg/m³7000 kg/m³
Melting point1854.85 °C301.85 °C
Boiling point4408.85 °C-273.15 °C
Discovery year17891940