Discovered By: Carl Gustaf Mosander
Discovery year: 1839

The following table showing some properties of Lanthanum(La):

Table Example
Atomic number 57
Group n/a
Period 6
Block f
Electrons 57
Protons 57
Neutrons 82
Atomic weight 138.90547
Oxidation states +3
Ionic charge La^3+


Table Example
Electrons per shell K2 L8 M18 N18 O9 P2
Electron configuration 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^10 4p^6 5s^2 4d^10 5p^6 6s^2 5d^1
Covalent radius 207 pm
Boiling point 3464°C
Melting point 920°C
Phase Solid
Fusion heat 6.2 kJ.mol^-1
Specific heat 195 J.kg^-1.K^-1
Thermal expansion 1.21*10^-5 K^-1
Vaporization heat 400 kJ.mol^-1


Table Example
Color Silver
Brinell hardness 363 MPa
Bulk modulus 28 GPa
Density 6146 kg.m^-3
Liquid density 5940 kg.m^-3
Mohs hardness 2.5
Poisson ratio 0.28
Shear modulus 14 GPa
Sound speed 2475 m.s^-1
Vickers hardness 491 MPa


Table Example
Young's modulus 37 GPa
Electrical type Conductor
Magnetic type Paramagnetic
Resistivity 6.1*10^-7 Ohm.m
Superconducting point 4.88 K
Electronegativity 1.1
Valence 3
Electron affinity 48 kJ.mol^-1
First ionization energy 538.1 kJ.mol^-1
Radioactive No
Neutron cross section 8.98 barn