Protactinium vs Dubnium

PropertyPa ProtactiniumDb Dubnium
Atomic number91105
SymbolPaDb
NameProtactiniumDubnium
Categoryactinidetransition-metal
Standard Atomic Weight231.03588 u268 u
Period77
GroupN/A5
Blockss
Phase at STPsolidN/A
Electron configuration[Rn]7s25f26d1[Rn]7s25f146d3
Oxidation states[2, 3, 4, 5][3, 4, 5]
Electronegativity (Pauling)1.5N/A
Electron affinity0.123 eV0.56 eV
Density1.537000e+4 kg/m³2.930000e+4 kg/m³
Melting point1571.85 °C-273.15 °C
Boiling point-273.15 °C-273.15 °C
Discovery year19131967