Cesium vs Erbium

PropertyCs CesiumEr Erbium
Atomic number5568
SymbolCsEr
NameCesiumErbium
Categoryalkali-metallanthanide
Standard Atomic Weight132.905452 u167.259 u
Period66
Group1N/A
Blockss
Phase at STPsolidsolid
Electron configuration[Xe]6s1[Xe]6s24f12
Oxidation states[-1, 1][0, 1, 2, 3]
Electronegativity (Pauling)0.791.24
Electron affinity0.4716 eV0.312 eV
Density1930 kg/m³9070 kg/m³
Melting point28.44 °C1528.85 °C
Boiling point670.85 °C2867.85 °C
Discovery year18601843