Properties of Thorium and Europium
Melting Point
1,750.00 °C
  
17
Boiling Point
1,597.00 °C
  
99+
Hardness
  
  
Mohs Hardness
Not Available
  
Brinell Hardness
Not Available
  
Optical Properties
  
  
Refractive Index
Not Available
  
Not Available
  
Reflectivity
Not Available
  
Not Available
  
Speed of Sound
2,490.00 m/s
  
36
Not Available
  
Allotropes
No
  
No
  
α Allotropes
Not Available
  
Not Available
  
β Allotropes
Not Available
  
Not Available
  
γ Allotropes
Not Available
  
Not Available
  
Chemical Formula
Th
  
Eu
  
Isotopes
  
  
Electronegativity
  
  
Pauling Electronegativity
Sanderson Electronegativity
Not Available
  
Allred Rochow Electronegativity
Not Available
  
Mulliken-Jaffe Electronegativity
Not Available
  
Not Available
  
Allen Electronegativity
Not Available
  
Not Available
  
Electropositivity
  
  
Pauling Electropositivity
Not Available
  
Ionization Energies
  
  
1st Energy Level
587.00 kJ/mol
  
99+
547.10 kJ/mol
  
99+
2nd Energy Level
1,110.00 kJ/mol
  
99+
1,085.00 kJ/mol
  
99+
3rd Energy Level
1,978.00 kJ/mol
  
99+
2,404.00 kJ/mol
  
99+
Electrochemical Equivalent
2.16 g/amp-hr
  
24
1.89 g/amp-hr
  
33
Other Chemical Properties
Density
  
  
Density At Room Temperature
11.72 g/cm3
  
32
5.26 g/cm3
  
99+
Density When Liquid (at m.p.)
Not Available
  
5.13 g/cm3
  
99+
Vapor Pressure
  
  
Vapor Pressure at 1000 K
Not Available
  
Vapor Pressure at 2000 K
Not Available
  
Tensile Strength
Not Available
  
Viscosity
Not Available
  
Not Available
  
Elasticity properties
  
  
Other Mechanical Properties
Symbol
Th
  
Eu
  
Group Number
Not Available
  
Period Number
7
  
6
  
Atomic Weight
151.96 amu
  
99+
Atomic Volume
19.90 cm3/mol
  
20
28.90 cm3/mol
  
8
Electron Configuration
[Rn] 6d2 7s2
  
[Xe] 4f7 6s2
  
Valence Electron Potential
59.30 (-eV)
  
23
45.60 (-eV)
  
35
Atom
  
  
Crystal Lattice
FCC-Crystal-Structure-of-Thorium.jpg#100
  
BCC-Crystal-Structure-.jpg#100
  
Radius of an Atom
  
  
Lattice Angles
π/2, π/2, π/2
  
π/2, π/2, π/2
  
Lattice C/A Ratio
Not Available
  
Not Available
  
Adjacent Atomic Numbers
  
  
Electrical Properties
  
  
Resistivity
157.00 nΩ·m
  
22
Electrical Conductivity
0.07 106/cm Ω
  
31
0.01 106/cm Ω
  
99+
Electron Affinity
Not Available
  
50.00 kJ/mol
  
21
Magnetic Characteristics
  
  
Permeability
Not Available
  
Not Available
  
Susceptibility
Not Available
  
Not Available
  
Specific Heat
0.12 J/(kg K)
  
40
0.18 J/(kg K)
  
33
Thermal Conductivity
54.00 W/m·K
  
28
13.90 W/m·K
  
99+
Critical Temperature
Not Available
  
Not Available
  
Molar Heat Capacity
26.23 J/mol·K
  
30
27.66 J/mol·K
  
16
Thermal Expansion
11.00 µm/(m·K)
  
36
35.00 µm/(m·K)
  
8
Standard Molar Entropy
27.30 J/mol.K
  
99+
77.80 J/mol.K
  
4
Enthalpy
  
  
Enthalpy of Vaporization
429.00 kJ/mol
  
15
143.50 kJ/mol
  
99+
Enthalpy of Fusion
15.48 kJ/mol
  
19
9.21 kJ/mol
  
37
Enthalpy of Atomization
468.60 kJ/mol
  
15
180.00 kJ/mol
  
99+