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Protactinium Iridium Comparison


Iridium Protactinium comparison


Periodic Table

Symbol
Pa   
Ir   

Group Number
Not Available   
9   
9

Period Number
7   
6   

Block
f block   
d block   

Element Family
Actinide   
Transition Metal   

CAS Number
7440133   
99+
7439885   
99+

Space Group Name
I4/mmm   
Fm_ 3m   

Space Group Number
139.00   
8
225.00   
2

Facts

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

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

History
  
  

Who Discovered
William Crookes   
Smithson Tennant   

Discovery
In 1900   
In 1803   

Abundance
  
  

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

Abundance In Sun
~-9999 %   
~0.0000002 %   
25

Abundance In Meteorites
Not Available   
0.00 %   
29

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

Abundance In Oceans
0.00 %   
99+
Not Available   

Uses

Uses & Benefits
  • Currently known uses of Protactinium metal are limited to research purpose only.
  
  • 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
NA   
Automobile Industry, Electrical Industry, Electronic Industry   

Medical Uses
NA   
NA   

Other Uses
NA   
Alloys   

Biological Properties
  
  

Toxicity
Highly Toxic   
Toxic   

Present in Human Body
No   
Yes   

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

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

Physical Properties

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

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

Appearance
  
  

Physical State
Solid   
Solid   

Color
Silver   
Silvery White   

Luster
Metallic   
Metallic   

Hardness
  
  

Mohs Hardness
Not Available   
6.50   
5

Brinell Hardness
Not Available   
1,670.00 MPa   
5

Vickers Hardness
Not Available   
1,760.00 MPa   
3

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

Optical Properties
  
  

Reflectivity
Not Available   
78.00 %   
6

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
Pa   
Ir   

Isotopes
  
  

Known Isotopes
27   
12
34   
5

Electronegativity
  
  

Pauling Electronegativity
1.50   
27
2.20   
4

Allred Rochow Electronegativity
1.14   
28
1.55   
11

Allen Electronegativity
Not Available   
1.68   
17

Electropositivity
  
  

Pauling Electropositivity
2.50   
27
1.80   
99+

Ionization Energies
  
  

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

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

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

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

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

Electron Work Function
Not Available   
4.55 eV   
13

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

Atomic Properties

Atomic Number
91   
27
77   
39

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

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

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

Atom
  
  

Number of Protons
91   
27
74   
99+

Number of Neutrons
122   
21
110   
27

Number of Electrons
91   
27
74   
99+

Radius of an Atom
  
  

Atomic Radius
163.00 pm   
25
136.00 pm   
99+

Covalent Radius
200.00 pm   
11
141.00 pm   
99+

Van der Waals Radius
243.00 pm   
11
202.00 pm   
27

Atomic Weight
231.04 amu   
24
192.22 amu   
34

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

Adjacent Atomic Numbers
  
  

Previous Element
Thorium
  
Osmium
  

Next Element
Uranium
  
Platinum
  

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

Lattice Constant
392.50 pm   
23
383.90 pm   
26

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
15.37 g/cm3   
20
22.56 g/cm3   
10

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

Tensile Strength
Not Available   
2,000.00 MPa   
2

Viscosity
Not Available   
Not Available   

Vapor Pressure
  
  

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

Elasticity properties
  
  

Shear Modulus
Not Available   
210.00 GPa   
2

Bulk Modulus
Not Available   
320.00 GPa   
3

Young's Modulus
Not Available   
528.00 GPa   
1

Poisson Ratio
Not Available   
0.26   
22

Other Mechanical Properties
Unknown   
NA   

Magnetic Properties

Magnetic Characteristics
  
  

Specific Gravity
15.37   
12
21.78   
3

Magnetic Ordering
Paramagnetic   
Paramagnetic   

Electrical Properties
  
  

Electrical Property
Conductor   
Conductor   

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

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

Electron Affinity
Not Available   
151.00 kJ/mol   
4

Thermal Properties

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

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

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

Critical Temperature
Not Available   
Not Available   

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

Enthalpy
  
  

Enthalpy of Vaporization
Not Available   
799.10 kJ/mol   
1

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

Enthalpy of Atomization
Not Available   
837.00 kJ/mol   
1

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

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