Properties of Tantalum and Osmium
Hardness
  
  
Brinell Hardness
3,490.00 MPa
  
1
Vickers Hardness
Not Available
  
Optical Properties
  
  
Refractive Index
Not Available
  
Not Available
  
Reflectivity
Not Available
  
Speed of Sound
3,400.00 m/s
  
22
4,940.00 m/s
  
11
Allotropes
No
  
No
  
α Allotropes
Not Available
  
Not Available
  
β Allotropes
Not Available
  
Not Available
  
γ Allotropes
Not Available
  
Not Available
  
Chemical Formula
Ta
  
Os
  
Isotopes
  
  
Electronegativity
  
  
Pauling Electronegativity
Sanderson Electronegativity
Not Available
  
Not Available
  
Allred Rochow Electronegativity
Mulliken-Jaffe Electronegativity
Not Available
  
Not Available
  
Electropositivity
  
  
Pauling Electropositivity
Ionization Energies
  
  
1st Energy Level
761.00 kJ/mol
  
18
840.00 kJ/mol
  
12
2nd Energy Level
1,500.00 kJ/mol
  
40
1,309.80 kJ/mol
  
99+
3rd Energy Level
Not Available
  
1,600.00 kJ/mol
  
99+
Electrochemical Equivalent
1.35 g/amp-hr
  
99+
1.77 g/amp-hr
  
38
Other Chemical Properties
Density
  
  
Density At Room Temperature
16.69 g/cm3
  
18
Density When Liquid (at m.p.)
Vapor Pressure
  
  
Vapor Pressure at 1000 K
Not Available
  
Not Available
  
Tensile Strength
Not Available
  
1,000.00 MPa
  
4
Viscosity
Not Available
  
Not Available
  
Elasticity properties
  
  
Young's Modulus
Not Available
  
Other Mechanical Properties
Symbol
Ta
  
Os
  
Period Number
6
  
6
  
Atomic Volume
10.90 cm3/mol
  
99+
8.49 cm3/mol
  
99+
Electron Configuration
[Xe] 4f14 5d3 6s2
  
[Xe] 4f14 5d6 6s2
  
Valence Electron Potential
110.00 (-eV)
  
7
91.40 (-eV)
  
12
Atom
  
  
Crystal Lattice
BCC-Crystal-Structure-.jpg#100
  
BCC-Crystal-Structure-.jpg#100
  
Radius of an Atom
  
  
Covalent Radius
Not Available
  
Lattice Angles
π/2, π/2, π/2
  
π/2, π/2, 2 π/3
  
Lattice C/A Ratio
Not Available
  
Adjacent Atomic Numbers
  
  
Electrical Properties
  
  
Resistivity
131.00 nΩ·m
  
25
Electrical Conductivity
0.08 106/cm Ω
  
27
0.11 106/cm Ω
  
18
Electron Affinity
31.00 kJ/mol
  
29
106.10 kJ/mol
  
9
Magnetic Characteristics
  
  
Permeability
Not Available
  
Not Available
  
Susceptibility
Not Available
  
Not Available
  
Specific Heat
0.14 J/(kg K)
  
37
0.13 J/(kg K)
  
39
Thermal Conductivity
57.50 W/m·K
  
27
87.60 W/m·K
  
19
Critical Temperature
Not Available
  
Not Available
  
Molar Heat Capacity
25.36 J/mol·K
  
99+
24.70 J/mol·K
  
99+
Thermal Expansion
6.30 µm/(m·K)
  
99+
5.10 µm/(m·K)
  
99+
Standard Molar Entropy
41.50 J/mol.K
  
37
32.60 J/mol.K
  
99+
Enthalpy
  
  
Enthalpy of Vaporization
753.10 kJ/mol
  
2
627.60 kJ/mol
  
7
Enthalpy of Fusion
31.40 kJ/mol
  
3
29.30 kJ/mol
  
4
Enthalpy of Atomization
782.00 kJ/mol
  
3
669.00 kJ/mol
  
6