Ytterbium vs Francium

PropertyYb YtterbiumFr Francium
Atomic number7087
SymbolYbFr
NameYtterbiumFrancium
Categorylanthanidealkali-metal
Standard Atomic Weight173.054 u223 u
Period67
GroupN/A1
Blockss
Phase at STPsolidsolid
Electron configuration[Xe]6s24f14[Rn]7s1
Oxidation states[0, 1, 2, 3][1]
Electronegativity (Pauling)N/A0.7
Electron affinity-0.02 eV0.491 eV
Density6900 kg/m³1870 kg/m³
Melting point818.85 °C26.85 °C
Boiling point1195.85 °C-273.15 °C
Discovery year18781939