Symbol
Os
  
Ir
  
Period Number
6
  
6
  
Block
d block
  
d block
  
Element Family
Transition Metal
  
Transition Metal
  
Space Group Name
P63/mmc
  
Fm_ 3m
  
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.
  
- Iridium element occurs as natural alloys of Platinum and Osmium.
- Iridium element is known as the most corrosion resistance metal .
  
Sources
Found As a By-product, Found in Minerals, Mining
  
Found in Minerals, Mining, Ores of Minerals
  
History
  
  
Who Discovered
Smithson Tennant
  
Smithson Tennant
  
Discovery
In 1803
  
In 1803
  
Abundance
  
  
Abundance In Sun
~0.0000002 %
  
25
~0.0000002 %
  
25
Abundance In Earth's Crust
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.
  
- Iridium has an anti corrosion properties and it is used in special alloy with Osmium metal and that alloy is used in pen tips and compass bearings.
  
Industrial Uses
Aerospace Industry, Automobile Industry, Electrical Industry, Electronic Industry
  
Automobile Industry, Electrical Industry, Electronic Industry
  
Medical Uses
NA
  
NA
  
Other Uses
Alloys
  
Alloys
  
Biological Properties
  
  
Toxicity
Highly Toxic
  
Toxic
  
Present in Human Body
No
  
Yes
  
Boiling Point
4,527.00 °C
  
10
Appearance
  
  
Physical State
Solid
  
Solid
  
Color
Silvery Bluish-Gray
  
Silvery White
  
Luster
Metallic
  
Metallic
  
Hardness
  
  
Brinell Hardness
3,490.00 MPa
  
1
1,670.00 MPa
  
5
Vickers Hardness
Not Available
  
1,760.00 MPa
  
3
Speed of Sound
4,940.00 m/s
  
11
4,825.00 m/s
  
13
Optical Properties
  
  
Reflectivity
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
Os
  
Ir
  
Isotopes
  
  
Electronegativity
  
  
Pauling Electronegativity
Allred Rochow Electronegativity
Electropositivity
  
  
Pauling Electropositivity
Ionization Energies
  
  
1st Energy Level
840.00 kJ/mol
  
12
880.00 kJ/mol
  
9
2nd Energy Level
1,309.80 kJ/mol
  
99+
1,600.00 kJ/mol
  
35
3rd Energy Level
1,600.00 kJ/mol
  
99+
Not Available
  
Electrochemical Equivalent
1.77 g/amp-hr
  
38
1.14 g/amp-hr
  
99+
Other Chemical Properties
Chemical Stability, Ionization, Solubility
  
Flammable, Ionization, Radioactive Isotopes, Radioactivity
  
Electron Configuration
[Xe] 4f14 5d6 6s2
  
[Xe] 4f14 5d7 6s2
  
Crystal Structure
Hexagonal Close Packed (HCP)
  
Face Centered Cubic (FCC)
  
Crystal Lattice
BCC-Crystal-Structure-.jpg#100
  
FCC-Crystal-Structure-of-Iridium.jpg#100
  
Atom
  
  
Radius of an Atom
  
  
Covalent Radius
Not Available
  
Atomic Volume
8.49 cm3/mol
  
99+
9.53 cm3/mol
  
99+
Adjacent Atomic Numbers
  
  
Valence Electron Potential
91.40 (-eV)
  
12
140.00 (-eV)
  
5
Lattice Angles
π/2, π/2, 2 π/3
  
π/2, π/2, π/2
  
Lattice C/A Ratio
Not Available
  
Density
  
  
Density At Room Temperature
22.56 g/cm3
  
10
Density When Liquid (at m.p.)
Tensile Strength
1,000.00 MPa
  
4
2,000.00 MPa
  
2
Viscosity
Not Available
  
Not Available
  
Vapor Pressure
  
  
Elasticity properties
  
  
Young's Modulus
Not Available
  
Other Mechanical Properties
Ductile
  
NA
  
Magnetic Characteristics
  
  
Magnetic Ordering
Paramagnetic
  
Paramagnetic
  
Electrical Properties
  
  
Electrical Property
Conductor
  
Conductor
  
Resistivity
47.10 nΩ·m
  
99+
Electrical Conductivity
0.11 106/cm Ω
  
18
0.19 106/cm Ω
  
10
Electron Affinity
106.10 kJ/mol
  
9
151.00 kJ/mol
  
4
Specific Heat
0.13 J/(kg K)
  
39
0.13 J/(kg K)
  
39
Molar Heat Capacity
24.70 J/mol·K
  
99+
25.10 J/mol·K
  
99+
Thermal Conductivity
87.60 W/m·K
  
19
147.00 W/m·K
  
10
Critical Temperature
Not Available
  
Not Available
  
Thermal Expansion
5.10 µm/(m·K)
  
99+
6.40 µm/(m·K)
  
99+
Enthalpy
  
  
Enthalpy of Vaporization
627.60 kJ/mol
  
7
799.10 kJ/mol
  
1
Enthalpy of Fusion
29.30 kJ/mol
  
4
35.23 kJ/mol
  
1
Enthalpy of Atomization
669.00 kJ/mol
  
6
837.00 kJ/mol
  
1
Standard Molar Entropy
32.60 J/mol.K
  
99+
35.50 J/mol.K
  
99+