Radium vs Mendelevium

PropertyRa RadiumMd Mendelevium
Atomic number88101
SymbolRaMd
NameRadiumMendelevium
Categoryalkaline-earth-metalactinide
Standard Atomic Weight226 u258 u
Period77
Group2N/A
Blockss
Phase at STPsolidsolid
Electron configuration[Rn]7s2[Rn]7s25f13
Oxidation states[2][2, 3]
Electronegativity (Pauling)0.91.3
Electron affinity0.096 eV0.997 eV
Density5000 kg/m³1.030000e+4 kg/m³
Melting point699.85 °C826.85 °C
Boiling point1139.85 °C-273.15 °C
Discovery year18981955