Discovered By: Baron Carl Auer von Welsbach
Discovery year: 1885

The following table showing some properties of Praseodymium(Pr):

Table Example
Atomic number 59
Group n/a
Period 6
Block f
Electrons 59
Protons 59
Neutron 82
Atomic weight 140.90766
Oxidation states +3, +4
Ionic charge Pr^3+


Table Example
Electrons per shell K2 L8 M18 N21 O8 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 4f^3
Atomic radius 247 pm
Covalent radius 203 pm
Boiling point 3290°C
Melting point 931°C
Phase Solid
Fusion heat 6.9 kJ.mol^-1
Thermal expansion 6.7*10^-6 K^-1
Vaporization heat 330 kJ.mol^-1


Table Example
Color Silver
Brinell hardness 481 MPa
Bulk modulus 29 GPa
Density 6640 kg.m^-3
Liquid density 6500 kg.m^-3
Mohs hardness 1.4
Poisson ratio 0.28
Shear modulus 15 GPa
Sound speed 2280 m.s^-1
Thermal conductivity 13 W.m^-1.K^-1


Table Example
Vickers hardness 400 MPa
Young's modulus 37 GPa
Electrical type conductor
Magnetic type Paramagnetic
Resistivity 7.10^-7 Ohm.m
Electronegativity 1.13
Valence 4
Electron affinity 50 kJ.mol^-1
First ionization energy 527 kJ.mol^-1
Radioactive No
Neutron cross section 11.4 barn