H He
Li Be B C N O F Ne
Na Mg Al Si P S Cl Ar
K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr
Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe
Cs Ba La Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn
Fr Ra Ac Rf Db Sg Bh Hs Mt Ds Rg Cn Nh Fl Mc Lv Ts Og
Ce Pr[Nd]Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu
Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr
Electron Configuration: [Xe]6s2 4f4
Electronegativity: 1.14
Atomic Radius: 229 pm
Ionization Energy: 5.525 eV
Electron Affinity:
Oxidation States: 3
Standard State: Solid
Melting Point: 1294 K
Boiling Point: 3347 K
Density: 7.01 g/cm3
Family: Lanthanide
Year Discovered: 1885
Number of Neutrons: 84
Number of Protons: 60
Number of Electrons: 60
Number of Valence:
Valency:
Group:
Period: 6
Shell: f-shell
Specific Heat: 0.190 J/g K
Radioactive: 0
Occurrence: Natural
Source: Dying low-mass stars
Source: Merging neutron stars