Promethium vs Flerovium

PropertyPm PromethiumFl Flerovium
Atomic number61114
SymbolPmFl
NamePromethiumFlerovium
Categorylanthanidepost-transition-metal
Standard Atomic Weight145 u289 u
Period67
GroupN/A14
Blocksp
Phase at STPsolidgas
Electron configuration[Xe]6s24f5[Rn] 7s27p2 5f14 6d10(predicted)
Oxidation states[2, 3][0, 1, 2, 4, 6]
Electronegativity (Pauling)N/AN/A
Electron affinity0.129 eV-0.5 eV
Density7260 kg/m³9928 kg/m³
Melting point1041.85 °C-273.15 °C
Boiling point2999.85 °C-63.15 °C
Discovery year19021998