Properties of Molybdenum and Thorium
Melting Point
1,750.00 °C
  
17
Hardness
  
  
Brinell Hardness
1,370.00 MPa
  
7
Vickers Hardness
1,400.00 MPa
  
6
Optical Properties
  
  
Refractive Index
Not Available
  
Not Available
  
Reflectivity
Not Available
  
Speed of Sound
5,400.00 m/s
  
6
2,490.00 m/s
  
36
Allotropes
No
  
No
  
α Allotropes
Not Available
  
Not Available
  
β Allotropes
Not Available
  
Not Available
  
γ Allotropes
Not Available
  
Not Available
  
Chemical Formula
Mo
  
Th
  
Isotopes
  
  
Electronegativity
  
  
Pauling Electronegativity
Sanderson Electronegativity
Not Available
  
Allred Rochow Electronegativity
Mulliken-Jaffe Electronegativity
Not Available
  
Not Available
  
Allen Electronegativity
Not Available
  
Electropositivity
  
  
Pauling Electropositivity
Ionization Energies
  
  
1st Energy Level
684.30 kJ/mol
  
37
587.00 kJ/mol
  
99+
2nd Energy Level
1,560.00 kJ/mol
  
37
1,110.00 kJ/mol
  
99+
3rd Energy Level
2,618.00 kJ/mol
  
99+
1,978.00 kJ/mol
  
99+
Electrochemical Equivalent
0.89 g/amp-hr
  
99+
2.16 g/amp-hr
  
24
Other Chemical Properties
Density
  
  
Density At Room Temperature
10.28 g/cm3
  
36
11.72 g/cm3
  
32
Density When Liquid (at m.p.)
Not Available
  
Vapor Pressure
  
  
Vapor Pressure at 1000 K
Not Available
  
Not Available
  
Tensile Strength
Not Available
  
Viscosity
Not Available
  
Not Available
  
Elasticity properties
  
  
Other Mechanical Properties
Symbol
Mo
  
Th
  
Period Number
5
  
7
  
Atomic Volume
9.40 cm3/mol
  
99+
19.90 cm3/mol
  
20
Electron Configuration
[Kr] 4d5 5s1
  
[Rn] 6d2 7s2
  
Valence Electron Potential
88.60 (-eV)
  
13
59.30 (-eV)
  
23
Atom
  
  
Crystal Lattice
BCC-Crystal-Structure-.jpg#100
  
FCC-Crystal-Structure-of-Thorium.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
53.40 nΩ·m
  
99+
157.00 nΩ·m
  
22
Electrical Conductivity
0.19 106/cm Ω
  
11
0.07 106/cm Ω
  
31
Electron Affinity
71.90 kJ/mol
  
14
Not Available
  
Magnetic Characteristics
  
  
Permeability
Not Available
  
Not Available
  
Susceptibility
Not Available
  
Not Available
  
Specific Heat
0.25 J/(kg K)
  
21
0.12 J/(kg K)
  
40
Thermal Conductivity
138.00 W/m·K
  
12
54.00 W/m·K
  
28
Critical Temperature
Not Available
  
Not Available
  
Molar Heat Capacity
24.06 J/mol·K
  
99+
26.23 J/mol·K
  
30
Thermal Expansion
4.80 µm/(m·K)
  
99+
11.00 µm/(m·K)
  
36
Standard Molar Entropy
28.70 J/mol.K
  
99+
27.30 J/mol.K
  
99+
Enthalpy
  
  
Enthalpy of Vaporization
594.10 kJ/mol
  
8
429.00 kJ/mol
  
15
Enthalpy of Fusion
27.61 kJ/mol
  
5
15.48 kJ/mol
  
19
Enthalpy of Atomization
653.00 kJ/mol
  
7
468.60 kJ/mol
  
15