Zirconium vs Fermium

PropertyZr ZirconiumFm Fermium
Atomic number40100
SymbolZrFm
NameZirconiumFermium
Categorytransition-metalactinide
Standard Atomic Weight91.224 u257 u
Period57
Group4N/A
Blockss
Phase at STPsolidsolid
Electron configuration[Kr]5s24d2[Rn] 5f12 7s2
Oxidation states[1, 2, 3, 4][2, 3]
Electronegativity (Pauling)1.331.3
Electron affinity0.426 eV0.339 eV
Density6520 kg/m³9700 kg/m³
Melting point1854.85 °C1526.85 °C
Boiling point4408.85 °C-273.15 °C
Discovery year17891952