Lanthanum
Atomic number
57
Atomic weight
138.9055
Discovery (year)
1839
Atomic radius (A)
1.88
Melting point (
o
C)
@
Boiling point (
o
C)
@
Density (g/cm
3
)
6.15
Specific heat (cal/g
o
C)
0.045
Ionization potential (eV)
5.577
Electron Affinity (eV)
0.5
