Ruthenium vs Cerium

PropertyRu RutheniumCe Cerium
Atomic number4458
SymbolRuCe
NameRutheniumCerium
Categorytransition-metallanthanide
Standard Atomic Weight101.07 u140.116 u
Period56
Group8N/A
Blockss
Phase at STPsolidsolid
Electron configuration[Kr]5s14d7[Xe]6s24f15d1
Oxidation states[-4, -2, 1, 2, 3, 4, 5, 6, 7, 8][1, 2, 3, 4]
Electronegativity (Pauling)2.21.12
Electron affinity1.05 eV0.955 eV
Density1.210000e+4 kg/m³6770 kg/m³
Melting point2333.85 °C797.85 °C
Boiling point4149.85 °C3423.85 °C
Discovery year18281801