Praseodymium
Symbol
Pr
Atomic Number
59
Atomic Weight
140.90765
Element Classification
Discovered By
C.F. Aver von Welsbach
Discovery Date
1885 (Austria)
Name Origin
Greek: prasios and didymos (green twin), from its green salts.
Density(g/cc)
6.773
Melting Point
1204
Boiling Point(K)
3785
Appearance
Silvery white, moderately soft, malleable, and ductile metal
Atomic Radius(pm)
182
Atomic Volume(cc/mol)
20.8
Covalent Radius(pm)
165
Ionic Radius
90 (+4e) 101.3 (+3e)
Specific Heat
0.192
Fusion Heat
11.3
Evaporation Heat(kj/mol)
331
Thermal Conductivity(@25°C W/m K)
12.5
Debye Temperature
n/a
Pauling Negativity Number
1.13
First Ionizing Energy(kj/mol)
526.6
Oxidation States
4, 3
Electronic Configuration
[Xe] 4f3 6s2
Lattice Structure
Hexagonal(HEX)
Lattice Constant
3.670
Lattice C/A Ratio
1.614
