Properties of Cerium and Praseodymium
Boiling Point
3,257.00 °C
  
23
3,130.00 °C
  
27
Hardness
  
  
Mohs Hardness
Not Available
  
Brinell Hardness
186.00 MPa
  
99+
Optical Properties
  
  
Refractive Index
Not Available
  
Not Available
  
Reflectivity
Not Available
  
Not Available
  
Speed of Sound
2,100.00 m/s
  
99+
2,280.00 m/s
  
40
Allotropes
No
  
No
  
α Allotropes
Not Available
  
Not Available
  
β Allotropes
Not Available
  
Not Available
  
γ Allotropes
Not Available
  
Not Available
  
Chemical Formula
Ce
  
Pr
  
Isotopes
  
  
Electronegativity
  
  
Pauling Electronegativity
Sanderson Electronegativity
Not Available
  
Not Available
  
Allred Rochow Electronegativity
Mulliken-Jaffe Electronegativity
Not Available
  
Not Available
  
Allen Electronegativity
Not Available
  
Not Available
  
Electropositivity
  
  
Pauling Electropositivity
Ionization Energies
  
  
1st Energy Level
534.40 kJ/mol
  
99+
527.00 kJ/mol
  
99+
2nd Energy Level
1,050.00 kJ/mol
  
99+
1,020.00 kJ/mol
  
99+
3rd Energy Level
1,949.00 kJ/mol
  
99+
2,086.00 kJ/mol
  
99+
Electrochemical Equivalent
1.74 g/amp-hr
  
99+
1.75 g/amp-hr
  
40
Other Chemical Properties
Density
  
  
Density At Room Temperature
6.77 g/cm
3
  
99+
6.77 g/cm
3
  
99+
Density When Liquid (at m.p.)
Vapor Pressure
  
  
Tensile Strength
Not Available
  
Not Available
  
Viscosity
Not Available
  
Not Available
  
Elasticity properties
  
  
Other Mechanical Properties
Symbol
Ce
  
Pr
  
Group Number
Not Available
  
Not Available
  
Period Number
6
  
6
  
Atomic Weight
140.12 amu
  
99+
140.91 amu
  
99+
Atomic Volume
20.67 cm3/mol
  
17
20.80 cm3/mol
  
15
Electron Configuration
[Xe] 4f1 5d1 6s2
  
[Xe] 4f3 6s2
  
Valence Electron Potential
41.78 (-eV)
  
99+
42.64 (-eV)
  
99+
Atom
  
  
Crystal Lattice
DHCP-Crystal-Structure-of-Cerium.jpg#100
  
HCP-Crystal-Structure-of-Praseodymium.jpg#100
  
Radius of an Atom
  
  
Lattice Angles
π/2, π/2, 2 π/3
  
π/2, π/2, 2 π/3
  
Lattice C/A Ratio
Not Available
  
Adjacent Atomic Numbers
  
  
Electrical Properties
  
  
Electrical Conductivity
0.01 106/cm Ω
  
99+
0.01 106/cm Ω
  
99+
Electron Affinity
50.00 kJ/mol
  
21
50.00 kJ/mol
  
21
Magnetic Characteristics
  
  
Permeability
Not Available
  
Not Available
  
Susceptibility
Not Available
  
Not Available
  
Specific Heat
0.19 J/(kg K)
  
32
0.19 J/(kg K)
  
32
Thermal Conductivity
11.30 W/m·K
  
99+
12.50 W/m·K
  
99+
Critical Temperature
Not Available
  
Not Available
  
Molar Heat Capacity
26.94 J/mol·K
  
23
27.20 J/mol·K
  
18
Thermal Expansion
6.30 µm/(m·K)
  
99+
6.70 µm/(m·K)
  
99+
Standard Molar Entropy
72.00 J/mol.K
  
12
73.20 J/mol.K
  
10
Enthalpy
  
  
Enthalpy of Vaporization
414.00 kJ/mol
  
16
296.80 kJ/mol
  
29
Enthalpy of Fusion
5.46 kJ/mol
  
99+
6.89 kJ/mol
  
99+
Enthalpy of Atomization
381.00 kJ/mol
  
23
368.00 kJ/mol
  
24