Einsteinium vs Meitnerium

PropertyEs EinsteiniumMt Meitnerium
Atomic number99109
SymbolEsMt
NameEinsteiniumMeitnerium
Categoryactinidetransition-metal
Standard Atomic Weight252 u278 u
Period77
GroupN/A9
Blockss
Phase at STPsolidN/A
Electron configuration[Rn]7s25f11[Rn]7s25f146d7(calculated)
Oxidation states[2, 3, 4][1, 3, 4, 6, 8, 9]
Electronegativity (Pauling)1.3N/A
Electron affinity-0.3 eV1.7 eV
Density8840 kg/m³3.740000e+4 kg/m³
Melting point859.85 °C-273.15 °C
Boiling point-273.15 °C-273.15 °C
Discovery year19521982