Iridium Hafnium Comparison
Periodic Table
Symbol
Ir
Hf
Group Number
9
9
4
14
Period Number
6
6
Block
d block
d block
Element Family
Transition Metal
Transition Metal
CAS Number
7439885
99+
7440586
30
Space Group Name
Fm_ 3m
P63/mmc
Space Group Number
225.00
2
194.00
5
Facts
Interesting Facts
- Iridium element occurs as natural alloys of Platinum and Osmium.
- Iridium element is known as the most corrosion resistance metal .
- Hafnium metal is highly reactive, hence not found free in nature.
- Hafnium metal as predicated after Mendeleev finished his periodic table.
Sources
Found in Minerals, Mining, Ores of Minerals
By-product Zirconium Refining
History
Who Discovered
Smithson Tennant
Dirk Coster and George de Hevesy
Discovery
In 1803
In 1922
Abundance
Abundance In Universe
2 * 10-7 %
22
7 * 10-8 %
25
Abundance In Sun
~0.0000002 %
25
~0.0000001 %
26
Abundance In Meteorites
0.00 %
29
0.00 %
37
Abundance In Earth's Crust
0.00 %
99+
0.00 %
31
Abundance In Oceans
Not Available
0.00 %
27
Uses
Uses & Benefits
- 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.
- It has an ability to absorb neutrons and hence it is used to make control rods in nuclear submarines. And this metal is also used in Plasma welding torches.
- It alloys with iron, titanium and niobium are very useful.
Industrial Uses
Automobile Industry, Electrical Industry, Electronic Industry
Ammunition Industry
Medical Uses
NA
NA
Other Uses
Alloys
Alloys, In Nuclear Reactors, Nuclear Research, Research Purposes
Biological Properties
Toxicity
Toxic
Toxic
Present in Human Body
Yes
No
Physical Properties
Melting Point
2,410.00 °C
7
2,150.00 °C
10
Boiling Point
4,527.00 °C
10
5,400.00 °C
5
Appearance
Physical State
Solid
Solid
Color
Silvery White
Gray
Luster
Metallic
Metallic
Hardness
Mohs Hardness
6.50
5
5.50
7
Brinell Hardness
1,670.00 MPa
5
1,450.00 MPa
6
Vickers Hardness
1,760.00 MPa
3
1,520.00 MPa
5
Speed of Sound
4,825.00 m/s
13
3,010.00 m/s
27
Optical Properties
Reflectivity
78.00 %
6
Not Available
Allotropes
No
No
α Allotropes
Not Available
Not Available
β Allotropes
Not Available
Not Available
γ Allotropes
Not Available
Not Available
Chemical Properties
Chemical Formula
Ir
Hf
Isotopes
Known Isotopes
34
5
32
7
Electronegativity
Pauling Electronegativity
2.20
4
1.30
32
Allred Rochow Electronegativity
1.55
11
1.23
25
Allen Electronegativity
1.68
17
1.16
37
Electropositivity
Pauling Electropositivity
1.80
99+
2.70
22
Ionization Energies
1st Energy Level
880.00 kJ/mol
9
658.50 kJ/mol
40
2nd Energy Level
1,600.00 kJ/mol
35
1,440.00 kJ/mol
99+
3rd Energy Level
Not Available
2,250.00 kJ/mol
99+
4th Energy Level
Not Available
3,216.00 kJ/mol
99+
Electrochemical Equivalent
1.14 g/amp-hr
99+
1.66 g/amp-hr
99+
Electron Work Function
4.55 eV
13
3.90 eV
27
Other Chemical Properties
Flammable, Ionization, Radioactive Isotopes, Radioactivity
Anti Corrosion, Ionization, Radioactive Isotopes, Solubility
Atomic Properties
Atomic Number
77
39
72
99+
Electron Configuration
[Xe] 4f14 5d7 6s2
[Xe] 4f14 5d2 6s2
Crystal Structure
Face Centered Cubic (FCC)
Hexagonal Close Packed (HCP)
Crystal Lattice
FCC-Crystal-Structure-of-Iridium.jpg#100
BCC-Crystal-Structure-.jpg#100
Atom
Number of Protons
74
99+
72
99+
Number of Neutrons
110
27
106
29
Number of Electrons
74
99+
72
99+
Radius of an Atom
Atomic Radius
136.00 pm
99+
159.00 pm
28
Covalent Radius
141.00 pm
99+
175.00 pm
23
Van der Waals Radius
202.00 pm
27
200.00 pm
28
Atomic Weight
192.22 amu
34
178.49 amu
39
Atomic Volume
9.53 cm3/mol
99+
13.60 cm3/mol
38
Adjacent Atomic Numbers
Valence Electron Potential
140.00 (-eV)
5
81.00 (-eV)
16
Lattice Constant
383.90 pm
26
319.64 pm
99+
Lattice Angles
π/2, π/2, π/2
π/2, π/2, 2 π/3
Lattice C/A Ratio
Not Available
1.58
12
Mechanical Properties
Density
Density At Room Temperature
22.56 g/cm3
10
13.31 g/cm3
26
Density When Liquid (at m.p.)
19.00 g/cm3
3
12.00 g/cm3
12
Tensile Strength
2,000.00 MPa
2
445.00 MPa
8
Viscosity
Not Available
Not Available
Vapor Pressure
Vapor Pressure at 2000 K
0.00 (Pa)
25
0.00 (Pa)
24
Elasticity properties
Shear Modulus
210.00 GPa
2
30.00 GPa
23
Bulk Modulus
320.00 GPa
3
110.00 GPa
15
Young's Modulus
528.00 GPa
1
78.00 GPa
25
Poisson Ratio
0.26
22
0.37
7
Other Mechanical Properties
NA
Ductile, Malleable
Magnetic Properties
Magnetic Characteristics
Specific Gravity
21.78
3
13.31
18
Magnetic Ordering
Paramagnetic
Paramagnetic
Electrical Properties
Electrical Property
Conductor
Conductor
Resistivity
47.10 nΩ·m
99+
331.00 nΩ·m
14
Electrical Conductivity
0.19 106/cm Ω
10
0.03 106/cm Ω
39
Electron Affinity
151.00 kJ/mol
4
0.00 kJ/mol
40
Thermal Properties
Specific Heat
0.13 J/(kg K)
39
0.14 J/(kg K)
37
Molar Heat Capacity
25.10 J/mol·K
99+
25.73 J/mol·K
36
Thermal Conductivity
147.00 W/m·K
10
23.00 W/m·K
99+
Critical Temperature
Not Available
Not Available
Thermal Expansion
6.40 µm/(m·K)
99+
5.90 µm/(m·K)
99+
Enthalpy
Enthalpy of Vaporization
799.10 kJ/mol
1
661.10 kJ/mol
5
Enthalpy of Fusion
35.23 kJ/mol
1
25.10 kJ/mol
8
Enthalpy of Atomization
837.00 kJ/mol
1
703.00 kJ/mol
5
Standard Molar Entropy
35.50 J/mol.K
99+
43.60 J/mol.K
34
|
||
|
||
|
