Home
Compare Metals


Iridium Holmium Comparison


Holmium Iridium comparison


Periodic Table

Symbol
Ir   
Ho   

Group Number
9   
9
Not Available   

Period Number
6   
6   

Block
d block   
f block   

Element Family
Transition Metal   
Lanthanide   

CAS Number
7439885   
99+
7440600   
29

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 .
  
  • Holmium metal is very soft and malleable.
  • Holmium metal is well known for its corrosion resistivity.
  

Sources
Found in Minerals, Mining, Ores of Minerals   
Found in Minerals, Mining, Ores of Minerals   

History
  
  

Who Discovered
Smithson Tennant   
Marc Delafontaine   

Discovery
In 1803   
In 1878   

Abundance
  
  

Abundance In Universe
2 * 10-7 %   
22
5 * 10-8 %   
27

Abundance In Sun
~0.0000002 %   
25
~-9999 %   

Abundance In Meteorites
0.00 %   
29
0.00 %   
99+

Abundance In Earth's Crust
0.00 %   
99+
0.00 %   
38

Abundance In Oceans
Not Available   
0.00 %   
99+

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.
  
  • Holmium metal has an ability to absorb neutrons, so this metal is used in nuclear reactors to keep the chain reactions of elements under control.
  • Alloys of Holmium are used to produce Magnet.
  

Industrial Uses
Automobile Industry, Electrical Industry, Electronic Industry   
NA   

Medical Uses
NA   
NA   

Other Uses
Alloys   
Alloys, Nuclear Research   

Biological Properties
  
  

Toxicity
Toxic   
Low Toxic   

Present in Human Body
Yes   
No   

Physical Properties

Melting Point
2,410.00 °C   
7
1,461.00 °C   
30

Boiling Point
4,527.00 °C   
10
2,600.00 °C   
99+

Appearance
  
  

Physical State
Solid   
Solid   

Color
Silvery White   
Silvery White   

Luster
Metallic   
Metallic   

Hardness
  
  

Mohs Hardness
6.50   
5
Not Available   

Brinell Hardness
1,670.00 MPa   
5
746.00 MPa   
13

Vickers Hardness
1,760.00 MPa   
3
481.00 MPa   
23

Speed of Sound
4,825.00 m/s   
13
2,760.00 m/s   
30

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   
Ho   

Isotopes
  
  

Known Isotopes
34   
5
34   
5

Electronegativity
  
  

Pauling Electronegativity
2.20   
4
1.23   
37

Allred Rochow Electronegativity
1.55   
11
1.10   
30

Allen Electronegativity
1.68   
17
Not Available   

Electropositivity
  
  

Pauling Electropositivity
1.80   
99+
2.77   
17

Ionization Energies
  
  

1st Energy Level
880.00 kJ/mol   
9
581.00 kJ/mol   
99+

2nd Energy Level
1,600.00 kJ/mol   
35
1,140.00 kJ/mol   
99+

3rd Energy Level
Not Available   
2,204.00 kJ/mol   
99+

4th Energy Level
Not Available   
4,100.00 kJ/mol   
34

Electrochemical Equivalent
1.14 g/amp-hr   
99+
2.02 g/amp-hr   
29

Electron Work Function
4.55 eV   
13
Not Available   

Other Chemical Properties
Flammable, Ionization, Radioactive Isotopes, Radioactivity   
Chemical Stability, Anti Corrosion, Ionization, Radioactive Isotopes, Solubility   

Atomic Properties

Atomic Number
77   
39
67   
99+

Electron Configuration
[Xe] 4f14 5d7 6s2   
[Xe] 4f11 6s2   

Crystal Structure
Face Centered Cubic (FCC)   
Hexagonal Close Packed (HCP)   

Crystal Lattice
FCC-Crystal-Structure-of-Iridium.jpg#100   
HCP-Crystal-Structure-of-Holmium.jpg#100   

Atom
  
  

Number of Protons
74   
99+
67   
99+

Number of Neutrons
110   
27
98   
34

Number of Electrons
74   
99+
67   
99+

Radius of an Atom
  
  

Atomic Radius
136.00 pm   
99+
176.00 pm   
18

Covalent Radius
141.00 pm   
99+
192.00 pm   
17

Van der Waals Radius
202.00 pm   
27
216.00 pm   
24

Atomic Weight
192.22 amu   
34
164.93 amu   
99+

Atomic Volume
9.53 cm3/mol   
99+
18.70 cm3/mol   
24

Adjacent Atomic Numbers
  
  

Previous Element
Osmium
  
Dysprosium
  

Next Element
Platinum
  
Erbium
  

Valence Electron Potential
140.00 (-eV)   
5
47.90 (-eV)   
31

Lattice Constant
383.90 pm   
26
357.73 pm   
38

Lattice Angles
π/2, π/2, π/2   
π/2, π/2, 2 π/3   

Lattice C/A Ratio
Not Available   
1.57   
17

Mechanical Properties

Density
  
  

Density At Room Temperature
22.56 g/cm3   
10
8.79 g/cm3   
99+

Density When Liquid (at m.p.)
19.00 g/cm3   
3
8.34 g/cm3   
26

Tensile Strength
2,000.00 MPa   
2
Not Available   

Viscosity
Not Available   
Not Available   

Vapor Pressure
  
  

Vapor Pressure at 1000 K
Not Available   
0.00 (Pa)   
16

Vapor Pressure at 2000 K
0.00 (Pa)   
25
Not Available   

Elasticity properties
  
  

Shear Modulus
210.00 GPa   
2
26.30 GPa   
28

Bulk Modulus
320.00 GPa   
3
40.20 GPa   
32

Young's Modulus
528.00 GPa   
1
64.80 GPa   
31

Poisson Ratio
0.26   
22
0.23   
29

Other Mechanical Properties
NA   
Ductile, Malleable, Sectile   

Magnetic Properties

Magnetic Characteristics
  
  

Specific Gravity
21.78   
3
8.80   
35

Magnetic Ordering
Paramagnetic   
Paramagnetic   

Electrical Properties
  
  

Electrical Property
Conductor   
Conductor   

Resistivity
47.10 nΩ·m   
99+
814.00 nΩ·m   
4

Electrical Conductivity
0.19 106/cm Ω   
10
0.01 106/cm Ω   
99+

Electron Affinity
151.00 kJ/mol   
4
50.00 kJ/mol   
21

Thermal Properties

Specific Heat
0.13 J/(kg K)   
39
0.16 J/(kg K)   
35

Molar Heat Capacity
25.10 J/mol·K   
99+
27.15 J/mol·K   
19

Thermal Conductivity
147.00 W/m·K   
10
16.20 W/m·K   
99+

Critical Temperature
Not Available   
Not Available   

Thermal Expansion
6.40 µm/(m·K)   
99+
11.20 µm/(m·K)   
35

Enthalpy
  
  

Enthalpy of Vaporization
799.10 kJ/mol   
1
241.00 kJ/mol   
38

Enthalpy of Fusion
35.23 kJ/mol   
1
11.76 kJ/mol   
29

Enthalpy of Atomization
837.00 kJ/mol   
1
301.00 kJ/mol   
36

Standard Molar Entropy
35.50 J/mol.K   
99+
75.30 J/mol.K   
8

Summary >>
<< Thermal

Compare Transition Metals

Transition Metals

Transition Metals

» More Transition Metals

Compare Transition Metals

» More Compare Transition Metals