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Osmium vs Protactinium


Protactinium vs Osmium


Periodic Table

Symbol
Os   
Pa   

Group Number
8   
10
Not Available   

Period Number
6   
7   

Block
d block   
f block   

Element Family
Transition Metal   
Actinide   

CAS Number
7440042   
99+
7440133   
99+

Space Group Name
P63/mmc   
I4/mmm   

Space Group Number
194.00   
5
139.00   
8

Facts

Interesting Facts
  • Osmium metal does not oxidize in air unless it is heated.
  • But if it heated den it forms Osmium Tetroxide, which is highly toxic.
  
  • Protactinium metal has 29 isotopes.
  • Isotopes of Protactinium-231 used in nuclear weapon.
  

Sources
Found As a By-product, Found in Minerals, Mining   
Found in Uranium Ores, Mining, Ores of metals   

History
  
  

Who Discovered
Smithson Tennant   
William Crookes   

Discovery
In 1803   
In 1900   

Abundance
  
  

Abundance In Universe
3 * 10-7 %   
21
Not Available   

Abundance In Sun
~0.0000002 %   
25
~-9999 %   

Abundance In Meteorites
0.00 %   
28
Not Available   

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

Abundance In Oceans
Not Available   
0.00 %   
99+

Uses

Uses & Benefits
  • Its has very limited uses and its alloys are very hard and are used in the manufacturing of pen tips, pivots, needles and electrical contacts.
  • It is also used as industrial catalyst to speed up the chemical reaction.
  
  • Currently known uses of Protactinium metal are limited to research purpose only.
  

Industrial Uses
Aerospace Industry, Automobile Industry, Electrical Industry, Electronic Industry   
NA   

Medical Uses
NA   
NA   

Other Uses
Alloys   
NA   

Biological Properties
  
  

Toxicity
Highly Toxic   
Highly Toxic   

Present in Human Body
No   
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
3,045.00 °C   
3
1,568.00 °C   
21

Boiling Point
5,027.00 °C   
6
4,027.00 °C   
12

Appearance
  
  

Physical State
Solid   
Solid   

Color
Silvery Bluish-Gray   
Silver   

Luster
Metallic   
Metallic   

Hardness
  
  

Mohs Hardness
7.00   
3
Not Available   

Brinell Hardness
3,490.00 MPa   
1
Not Available   

Speed of Sound
4,940.00 m/s   
11
Not Available   

Optical Properties
  
  

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
Os   
Pa   

Isotopes
  
  

Known Isotopes
35   
4
27   
12

Electronegativity
  
  

Pauling Electronegativity
2.20   
4
1.50   
27

Allred Rochow Electronegativity
1.52   
12
1.14   
28

Allen Electronegativity
1.65   
19
Not Available   

Electropositivity
  
  

Pauling Electropositivity
1.80   
99+
2.50   
27

Ionization Energies
  
  

1st Energy Level
840.00 kJ/mol   
12
568.00 kJ/mol   
99+

2nd Energy Level
1,309.80 kJ/mol   
99+
1,128.00 kJ/mol   
99+

3rd Energy Level
1,600.00 kJ/mol   
99+
1,814.00 kJ/mol   
99+

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

Electrochemical Equivalent
1.77 g/amp-hr   
38
1.72 g/amp-hr   
99+

Electron Work Function
4.83 eV   
8
Not Available   

Other Chemical Properties
Chemical Stability, Ionization, Solubility   
Ionization, Radioactive Isotopes, Radioactivity   

Atomic Properties

Atomic Number
76   
40
91   
27

Electron Configuration
[Xe] 4f14 5d6 6s2   
[Rn] 5f2 6d1 7s2   

Crystal Structure
Hexagonal Close Packed (HCP)   
Tetragonal (TETR)   

Crystal Lattice
BCC-Crystal-Structure-.jpg#100   
TETR-Crystal-Structure-of-Protactinium.jpg#100   

Atom
  
  

Number of Protons
76   
39
91   
27

Number of Neutrons
114   
25
122   
21

Number of Electrons
76   
39
91   
27

Radius of an Atom
  
  

Atomic Radius
133.80 pm   
99+
163.00 pm   
25

Covalent Radius
Not Available   
200.00 pm   
11

Van der Waals Radius
216.00 pm   
24
243.00 pm   
11

Atomic Weight
190.23 amu   
35
231.04 amu   
24

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

Adjacent Atomic Numbers
  
  

Previous Element
Rhenium
  
Thorium
  

Next Element
Iridium
  
Uranium
  

Valence Electron Potential
91.40 (-eV)   
12
92.00 (-eV)   
11

Lattice Constant
273.44 pm   
99+
392.50 pm   
23

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

Lattice C/A Ratio
1.58   
14
Not Available   

Mechanical Properties

Density
  
  

Density At Room Temperature
22.59 g/cm3   
9
15.37 g/cm3   
20

Density When Liquid (at m.p.)
20.00 g/cm3   
1
Not Available   

Tensile Strength
1,000.00 MPa   
4
Not Available   

Viscosity
Not Available   
Not Available   

Vapor Pressure
  
  

Vapor Pressure at 2000 K
0.00 (Pa)   
28
Not Available   

Elasticity properties
  
  

Shear Modulus
222.00 GPa   
1
Not Available   

Bulk Modulus
462.00 GPa   
1
Not Available   

Poisson Ratio
0.25   
24
Not Available   

Other Mechanical Properties
Ductile   
Unknown   

Magnetic Properties

Magnetic Characteristics
  
  

Specific Gravity
22.57   
2
15.37   
12

Magnetic Ordering
Paramagnetic   
Paramagnetic   

Electrical Properties
  
  

Electrical Property
Conductor   
Conductor   

Resistivity
81.20 nΩ·m   
35
177.00 nΩ·m   
21

Electrical Conductivity
0.11 106/cm Ω   
18
0.05 106/cm Ω   
34

Electron Affinity
106.10 kJ/mol   
9
Not Available   

Thermal Properties

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

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

Thermal Conductivity
87.60 W/m·K   
19
47.00 W/m·K   
32

Critical Temperature
Not Available   
Not Available   

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

Enthalpy
  
  

Enthalpy of Vaporization
627.60 kJ/mol   
7
Not Available   

Enthalpy of Fusion
29.30 kJ/mol   
4
12.34 kJ/mol   
28

Enthalpy of Atomization
669.00 kJ/mol   
6
Not Available   

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

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