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Iridium vs Protactinium


Protactinium vs Iridium


Periodic Table

Symbol
Ir   
Pa   

Group Number
9   
9
Not Available   

Period Number
6   
7   

Block
d block   
f block   

Element Family
Transition Metal   
Actinide   

CAS Number
7439885   
99+
7440133   
99+

Space Group Name
Fm_ 3m   
I4/mmm   

Space Group Number
225.00   
2
139.00   
8

Facts

Interesting Facts
  • Iridium element occurs as natural alloys of Platinum and Osmium.
  • Iridium element is known as the most corrosion resistance metal .
  
  • Protactinium metal has 29 isotopes.
  • Isotopes of Protactinium-231 used in nuclear weapon.
  

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

History
  
  

Who Discovered
Smithson Tennant   
William Crookes   

Discovery
In 1803   
In 1900   

Abundance
  
  

Abundance In Universe
2 * 10-7 %   
22
Not Available   

Abundance In Sun
~0.0000002 %   
25
~-9999 %   

Abundance In Meteorites
0.00 %   
29
Not Available   

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

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.
  
  • Currently known uses of Protactinium metal are limited to research purpose only.
  

Industrial Uses
Automobile Industry, Electrical Industry, Electronic Industry   
NA   

Medical Uses
NA   
NA   

Other Uses
Alloys   
NA   

Biological Properties
  
  

Toxicity
Toxic   
Highly Toxic   

Present in Human Body
Yes   
No   

In Blood
Not Available   
0.00 Blood/mg dm-3   
37

In Bone
Not Available   
0.00 p.p.m.   
36

Physical Properties

Melting Point
2,410.00 °C   
7
1,568.00 °C   
21

Boiling Point
4,527.00 °C   
10
4,027.00 °C   
12

Appearance
  
  

Physical State
Solid   
Solid   

Color
Silvery White   
Silver   

Luster
Metallic   
Metallic   

Hardness
  
  

Mohs Hardness
6.50   
5
Not Available   

Brinell Hardness
1,670.00 MPa   
5
Not Available   

Vickers Hardness
1,760.00 MPa   
3
Not Available   

Speed of Sound
4,825.00 m/s   
13
Not Available   

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   
Pa   

Isotopes
  
  

Known Isotopes
34   
5
27   
12

Electronegativity
  
  

Pauling Electronegativity
2.20   
4
1.50   
27

Allred Rochow Electronegativity
1.55   
11
1.14   
28

Allen Electronegativity
1.68   
17
Not Available   

Electropositivity
  
  

Pauling Electropositivity
1.80   
99+
2.50   
27

Ionization Energies
  
  

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

2nd Energy Level
1,600.00 kJ/mol   
35
1,128.00 kJ/mol   
99+

3rd Energy Level
Not Available   
1,814.00 kJ/mol   
99+

4th Energy Level
Not Available   
2,991.00 kJ/mol   
99+

Electrochemical Equivalent
1.14 g/amp-hr   
99+
1.72 g/amp-hr   
99+

Electron Work Function
4.55 eV   
13
Not Available   

Other Chemical Properties
Flammable, Ionization, Radioactive Isotopes, Radioactivity   
Ionization, Radioactive Isotopes, Radioactivity   

Atomic Properties

Atomic Number
77   
39
91   
27

Electron Configuration
[Xe] 4f14 5d7 6s2   
[Rn] 5f2 6d1 7s2   

Crystal Structure
Face Centered Cubic (FCC)   
Tetragonal (TETR)   

Crystal Lattice
FCC-Crystal-Structure-of-Iridium.jpg#100   
TETR-Crystal-Structure-of-Protactinium.jpg#100   

Atom
  
  

Number of Protons
74   
99+
91   
27

Number of Neutrons
110   
27
122   
21

Number of Electrons
74   
99+
91   
27

Radius of an Atom
  
  

Atomic Radius
136.00 pm   
99+
163.00 pm   
25

Covalent Radius
141.00 pm   
99+
200.00 pm   
11

Van der Waals Radius
202.00 pm   
27
243.00 pm   
11

Atomic Weight
192.22 amu   
34
231.04 amu   
24

Atomic Volume
9.53 cm3/mol   
99+
15.00 cm3/mol   
34

Adjacent Atomic Numbers
  
  

Previous Element
Osmium
  
Thorium
  

Next Element
Platinum
  
Uranium
  

Valence Electron Potential
140.00 (-eV)   
5
92.00 (-eV)   
11

Lattice Constant
383.90 pm   
26
392.50 pm   
23

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

Lattice C/A Ratio
Not Available   
Not Available   

Mechanical Properties

Density
  
  

Density At Room Temperature
22.56 g/cm3   
10
15.37 g/cm3   
20

Density When Liquid (at m.p.)
19.00 g/cm3   
3
Not Available   

Tensile Strength
2,000.00 MPa   
2
Not Available   

Viscosity
Not Available   
Not Available   

Vapor Pressure
  
  

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

Elasticity properties
  
  

Shear Modulus
210.00 GPa   
2
Not Available   

Bulk Modulus
320.00 GPa   
3
Not Available   

Young's Modulus
528.00 GPa   
1
Not Available   

Poisson Ratio
0.26   
22
Not Available   

Other Mechanical Properties
NA   
Unknown   

Magnetic Properties

Magnetic Characteristics
  
  

Specific Gravity
21.78   
3
15.37   
12

Magnetic Ordering
Paramagnetic   
Paramagnetic   

Electrical Properties
  
  

Electrical Property
Conductor   
Conductor   

Resistivity
47.10 nΩ·m   
99+
177.00 nΩ·m   
21

Electrical Conductivity
0.19 106/cm Ω   
10
0.05 106/cm Ω   
34

Electron Affinity
151.00 kJ/mol   
4
Not Available   

Thermal Properties

Specific Heat
0.13 J/(kg K)   
39
0.12 J/(kg K)   
40

Molar Heat Capacity
25.10 J/mol·K   
99+
Not Available   

Thermal Conductivity
147.00 W/m·K   
10
47.00 W/m·K   
32

Critical Temperature
Not Available   
Not Available   

Thermal Expansion
6.40 µm/(m·K)   
99+
9.90 µm/(m·K)   
40

Enthalpy
  
  

Enthalpy of Vaporization
799.10 kJ/mol   
1
Not Available   

Enthalpy of Fusion
35.23 kJ/mol   
1
12.34 kJ/mol   
28

Enthalpy of Atomization
837.00 kJ/mol   
1
Not Available   

Standard Molar Entropy
35.50 J/mol.K   
99+
198.10 J/mol.K   
1

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