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Protactinium vs Iridium


Iridium vs Protactinium


Periodic Table

Symbol
Pa  
Ir  

Group Number
3  
15
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  
11
225.00  
3

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
0.00 %  
17
0.00 %  
23

Abundance In Sun
0.00 %  
26
0.00 %  
25

Abundance In Meteorites
-  
0.00 %  
29

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

Abundance In Oceans
0.00 %  
99+
-  

Abundance In Humans
0.00 %  
24
0.00 %  
24

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
-  
Automobile Industry, Electrical Industry, Electronic Industry  

Medical Uses
-  
-  

Other Uses
-  
Alloys  

Biological Properties
  
  

Toxicity
Highly Toxic  
Toxic  

Present in Human Body
No  
Yes  

In Blood
0.00 Blood/mg dm-3  
40
0.00 Blood/mg dm-3  
40

In Bone
0.00 p.p.m.  
99+
0.00 p.p.m.  
99+

Physical

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
5.00  
8
6.50  
5

Brinell Hardness
125.00 MPa  
99+
1,670.00 MPa  
5

Vickers Hardness
220.00 MPa  
99+
1,760.00 MPa  
8

Speed of Sound
12,400.00 m/s  
3
4,825.00 m/s  
17

Optical Properties
  
  

Refractive Index
1.60  
33
2.40  
7

Reflectivity
60.00 %  
23
78.00 %  
8

Allotropes
No  
No  

α Allotropes
-  
-  

β Allotropes
-  
-  

γ Allotropes
-  
-  

Chemical

Chemical Formula
Pa  
Ir  

Isotopes
  
  

Known Isotopes
27  
12
34  
5

Electronegativity
  
  

Pauling Electronegativity
1.50  
28
2.20  
5

Sanderson Electronegativity
1.50  
18
2.20  
8

Allred Rochow Electronegativity
1.14  
29
1.55  
12

Mulliken-Jaffe Electronegativity
1.50  
26
2.20  
6

Allen Electronegativity
1.50  
32
1.68  
20

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  
36

3rd Energy Level
1,814.00 kJ/mol  
99+
2,256.10 kJ/mol  
99+

4th Energy Level
2,991.00 kJ/mol  
99+
880.00 kJ/mol  
99+

5th Energy Level
5,120.00 kJ/mol  
99+
8,800.00 kJ/mol  
8

6th Energy Level
5,680.00 kJ/mol  
99+
8,800.00 kJ/mol  
25

7th Energy level
5,680.00 kJ/mol  
99+
8,800.00 kJ/mol  
22

8th Energy Level
5,680.00 kJ/mol  
99+
8,800.00 kJ/mol  
22

9th Energy Level
5,120.00 kJ/mol  
99+
8,800.00 kJ/mol  
21

10th Energy Level
5,120.00 kJ/mol  
99+
8,800.00 kJ/mol  
23

11th Energy Level
5,680.00 kJ/mol  
99+
8,800.00 kJ/mol  
20

12th Energy Level
5,680.00 kJ/mol  
99+
8,800.00 kJ/mol  
40

13th Energy Level
5,680.00 kJ/mol  
99+
8,800.00 kJ/mol  
15

14th Energy Level
5,680.00 kJ/mol  
99+
8,800.00 kJ/mol  
14

15th Energy Level
56,800.00 kJ/mol  
99+
88,000.00 kJ/mol  
8

16th Energy Level
56,800.00 kJ/mol  
99+
88,000.00 kJ/mol  
9

17th Energy Level
568.50 kJ/mol  
99+
880.00 kJ/mol  
26

18th Energy Level
5,680.00 kJ/mol  
99+
8,800.00 kJ/mol  
15

19th Energy Level
568.30 kJ/mol  
99+
880.00 kJ/mol  
24

20th Energy Level
568.00 kJ/mol  
99+
880.00 kJ/mol  
14

21st Energy Level
568.00 kJ/mol  
99+
880.00 kJ/mol  
37

22nd Energy Level
568.00 kJ/mol  
99+
880.00 kJ/mol  
12

23rd Energy Level
568.00 kJ/mol  
99+
8,800.00 kJ/mol  
7

24th Energy Level
568.00 kJ/mol  
99+
880.00 kJ/mol  
8

25th Energy Level
568.00 kJ/mol  
99+
880.00 kJ/mol  
6

26th Energy Level
568.00 kJ/mol  
99+
880.00 kJ/mol  
6

27th Energy Level
568.00 kJ/mol  
99+
880.00 kJ/mol  
5

28th Energy Level
568.00 kJ/mol  
99+
880.00 kJ/mol  
8

29th Energy Level
568.00 kJ/mol  
99+
880.00 kJ/mol  
9

30th Energy Level
568.00 kJ/mol  
99+
880.00 kJ/mol  
6

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

Electron Work Function
5.89 eV  
3
4.55 eV  
18

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

Atomic

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  
22
110  
28

Number of Electrons
91  
27
74  
99+

Radius of an Atom
  
  

Atomic Radius
163.00 pm  
27
136.00 pm  
99+

Covalent Radius
200.00 pm  
11
141.00 pm  
99+

Van der Waals Radius
243.00 pm  
15
202.00 pm  
34

Atomic Weight
231.04 amu  
24
192.22 amu  
34

Atomic Volume
15.00 cm3/mol  
99+
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  
26
383.90 pm  
29

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

Lattice C/A Ratio
1.58  
36
1.58  
35

Mechanical

Density
  
  

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

Density When Liquid (at m.p.)
15.37 g/cm3  
21
19.00 g/cm3  
13

Tensile Strength
80.00 MPa  
29
2,000.00 MPa  
2

Viscosity
0.00  
25
0.00  
21

Vapor Pressure
  
  

Vapor Pressure at 1000 K
0.00 (Pa)  
37
0.00 (Pa)  
37

Vapor Pressure at 2000 K
0.00 (Pa)  
32
0.00 (Pa)  
26

Elasticity properties
  
  

Shear Modulus
16.00 GPa  
99+
210.00 GPa  
2

Bulk Modulus
47.00 GPa  
26
320.00 GPa  
3

Young's Modulus
47.00 GPa  
99+
528.00 GPa  
1

Poisson Ratio
0.23  
30
0.26  
22

Other Mechanical Properties
-  
-  

Magnetic

Magnetic Characteristics
  
  

Specific Gravity
15.37  
23
21.78  
12

Magnetic Ordering
Paramagnetic  
Paramagnetic  

Permeability
0.00 H/m  
10
0.00 H/m  
16

Susceptibility
0.00  
21
0.00  
5

Electrical Properties
  
  

Electrical Property
Conductor  
Conductor  

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

Electrical Conductivity
0.05 106/cm Ω  
39
0.19 106/cm Ω  
10

Electron Affinity
53.03 kJ/mol  
22
151.00 kJ/mol  
4

Thermal

Specific Heat
0.12 J/(kg K)  
99+
0.13 J/(kg K)  
40

Molar Heat Capacity
27.20 J/mol·K  
24
25.10 J/mol·K  
99+

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

Critical Temperature
1,841.00 K  
25
2,719.00 K  
8

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

Enthalpy
  
  

Enthalpy of Vaporization
481.00 kJ/mol  
17
799.10 kJ/mol  
1

Enthalpy of Fusion
12.34 kJ/mol  
34
35.23 kJ/mol  
1

Enthalpy of Atomization
481.90 kJ/mol  
19
837.00 kJ/mol  
1

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

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