PERIODIC ELEMENT
La (Lanthanum)

 



Atomic number : 57
Atomic mass : 138.91 g.mol -1
Electronegativity according to Pauling : 1.1
Density : 6.18 g.cm-3 at 20 °C
Melting point : 826 °C
Boiling point : °C
Vanderwaals radius : 0.104 nm
Ionic radius : 0.186 nm
Isotopes : 7
Electronic shell : [ Xe ] 5d1 6s2
Energy of first ionisation : 539 kJ.mol-1
Energy of second ionisation : 1098 kJ.mol-1
Energy of third ionisation : 1840 kJ.mol-1
Standard Potential : - 2.52 V (La3+/ La)
Discovered by : Carl Mosander in 1839
 
Atomic Structure Uses(expensive camera lenses)