Symbol La Atomic radius: pm 187 Fusion: kJ/Mole 6.20
Name Lanthanum Ionic radius: pm (+3)116 Boiling point: C 3464
Atomic number 57 Electron affinity 0.5 Melting point: C 918
Atomic weight 138.9 1st  ion potential 5.77 Specific Heat Cap: J/(g K) 0.20
Classification Trans metal Natural form Solid Thermal Cond: W/(cm K) 0.13
Configuration [Xe]5d16s2 Crystal structure Hex Electrical Cond 0.0126
Oxidation states 3 Density 6.15 Abundance: mg/kg-crust 39
Electronegativity 1.10 Vaporization: kJ/Mole 399.6    
Lanthanum was discovered in 1839 by Carl Gustaf Mosander. Uses - lighter flints, studio lighting and projection, special optical glasses such as camera lenses