Symbol
Os
  
Tb
  
Group Number
Not Available
  
Period Number
6
  
6
  
Block
d block
  
f block
  
Element Family
Transition Metal
  
Lanthanide
  
Space Group Name
P63/mmc
  
P63/mmc
  
Interesting Facts
- Osmium metal does not oxidize in air unless it is heated.
- But if it heated den it forms Osmium Tetroxide, which is highly toxic.
  
- At times Terbium metal acts same as Calcium.
- Terbium metal closely similar to Lanthanum metal.
  
Sources
Found As a By-product, Found in Minerals, Mining
  
Found in Minerals, Found with Other Rare Earth Metals, Mining, Ores of Minerals
  
History
  
  
Who Discovered
Smithson Tennant
  
Carl Gustaf Mosander
  
Discovery
In 1803
  
In 1842
  
Abundance
  
  
Abundance In Sun
~0.0000002 %
  
25
~0.00000001 %
  
29
Abundance In Earth's Crust
Abundance In Oceans
Not Available
  
Uses & Benefits
- Its has very limited uses and its alloys are very hard and are used in the manufacturing of pen tips, pivots, needles and electrical contacts.
-
It is also used as industrial catalyst to speed up the chemical reaction.
  
- Terbium salts are used in optical devices like laser devices.
-
Terbium’s alloy lengthens and shortens the magnetic field and this effect forms loudspeaker.
  
Industrial Uses
Aerospace Industry, Automobile Industry, Electrical Industry, Electronic Industry
  
Electronic Industry
  
Medical Uses
NA
  
NA
  
Other Uses
Alloys
  
Alloys
  
Biological Properties
  
  
Toxicity
Highly Toxic
  
Low Toxic
  
Present in Human Body
No
  
No
  
Melting Point
1,356.00 °C
  
33
Boiling Point
3,123.00 °C
  
29
Appearance
  
  
Physical State
Solid
  
Solid
  
Color
Silvery Bluish-Gray
  
Silvery White
  
Luster
Metallic
  
Metallic
  
Hardness
  
  
Mohs Hardness
Not Available
  
Brinell Hardness
3,490.00 MPa
  
1
Vickers Hardness
Not Available
  
Speed of Sound
4,940.00 m/s
  
11
2,620.00 m/s
  
35
Optical Properties
  
  
Allotropes
No
  
No
  
α Allotropes
Not Available
  
Not Available
  
β Allotropes
Not Available
  
Not Available
  
γ Allotropes
Not Available
  
Not Available
  
Chemical Formula
Os
  
Tb
  
Isotopes
  
  
Electronegativity
  
  
Pauling Electronegativity
Not Available
  
Allred Rochow Electronegativity
Allen Electronegativity
Not Available
  
Electropositivity
  
  
Pauling Electropositivity
Not Available
  
Ionization Energies
  
  
1st Energy Level
840.00 kJ/mol
  
12
603.40 kJ/mol
  
99+
2nd Energy Level
1,309.80 kJ/mol
  
99+
1,174.80 kJ/mol
  
99+
3rd Energy Level
1,600.00 kJ/mol
  
99+
2,417.00 kJ/mol
  
99+
4th Energy Level
Not Available
  
4,203.00 kJ/mol
  
31
Electrochemical Equivalent
1.77 g/amp-hr
  
38
1.98 g/amp-hr
  
31
Other Chemical Properties
Chemical Stability, Ionization, Solubility
  
Ionization, Radioactive Isotopes, Solubility
  
Electron Configuration
[Xe] 4f14 5d6 6s2
  
[Xe] 4f9 6s2
  
Crystal Structure
Hexagonal Close Packed (HCP)
  
Hexagonal Close Packed (HCP)
  
Crystal Lattice
BCC-Crystal-Structure-.jpg#100
  
HCP-Crystal-Structure-of-Terbium.jpg#100
  
Atom
  
  
Radius of an Atom
  
  
Covalent Radius
Not Available
  
Atomic Weight
158.93 amu
  
99+
Atomic Volume
8.49 cm3/mol
  
99+
19.20 cm3/mol
  
22
Adjacent Atomic Numbers
  
  
Valence Electron Potential
91.40 (-eV)
  
12
46.80 (-eV)
  
33
Lattice Angles
π/2, π/2, 2 π/3
  
π/2, π/2, 2 π/3
  
Density
  
  
Density At Room Temperature
8.23 g/cm3
  
99+
Density When Liquid (at m.p.)
Tensile Strength
1,000.00 MPa
  
4
Viscosity
Not Available
  
Not Available
  
Vapor Pressure
  
  
Vapor Pressure at 1000 K
Not Available
  
Elasticity properties
  
  
Young's Modulus
Not Available
  
Other Mechanical Properties
Ductile
  
Ductile, Malleable
  
Magnetic Characteristics
  
  
Magnetic Ordering
Paramagnetic
  
Paramagnetic
  
Electrical Properties
  
  
Electrical Property
Conductor
  
Conductor
  
Electrical Conductivity
0.11 106/cm Ω
  
18
0.01 106/cm Ω
  
99+
Electron Affinity
106.10 kJ/mol
  
9
50.00 kJ/mol
  
21
Specific Heat
0.13 J/(kg K)
  
39
0.18 J/(kg K)
  
33
Molar Heat Capacity
24.70 J/mol·K
  
99+
28.91 J/mol·K
  
9
Thermal Conductivity
87.60 W/m·K
  
19
11.10 W/m·K
  
99+
Critical Temperature
Not Available
  
Not Available
  
Thermal Expansion
5.10 µm/(m·K)
  
99+
10.30 µm/(m·K)
  
38
Enthalpy
  
  
Enthalpy of Vaporization
627.60 kJ/mol
  
7
330.90 kJ/mol
  
26
Enthalpy of Fusion
29.30 kJ/mol
  
4
10.80 kJ/mol
  
34
Enthalpy of Atomization
669.00 kJ/mol
  
6
314.00 kJ/mol
  
33
Standard Molar Entropy
32.60 J/mol.K
  
99+
73.20 J/mol.K
  
10