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Roentgenium Hafnium Comparison


Hafnium Roentgenium comparison


Periodic Table

Symbol
Rg   
Hf   

Group Number
11   
7
4   
14

Period Number
7   
6   

Block
d block   
d block   

Element Family
Unknown   
Transition Metal   

CAS Number
54386242   
1
7440586   
30

Space Group Name
Not Available   
P63/mmc   

Space Group Number
194.00   
5
194.00   
5

Facts

Interesting Facts
Not Available   
  • Hafnium metal is highly reactive, hence not found free in nature.
  • Hafnium metal as predicated after Mendeleev finished his periodic table.
  

Sources
Synthetically Produced   
By-product Zirconium Refining   

History
  
  

Who Discovered
Gesellschaft für Schwerionenforschung   
Dirk Coster and George de Hevesy   

Discovery
In 1994   
In 1922   

Abundance
  
  

Abundance In Universe
Not Available   
7 * 10-8 %   
25

Abundance In Sun
~-9999 %   
~0.0000001 %   
26

Abundance In Meteorites
Not Available   
0.00 %   
37

Abundance In Earth's Crust
Not Available   
0.00 %   
31

Abundance In Oceans
Not Available   
0.00 %   
27

Uses

Uses & Benefits
  • Currently known uses of Roentgenium metal are limited to research purpose only.
  
  • It has an ability to absorb neutrons and hence it is used to make control rods in nuclear submarines. And this metal is also used in Plasma welding torches.
  • It alloys with iron, titanium and niobium are very useful.
  

Industrial Uses
NA   
Ammunition Industry   

Medical Uses
NA   
NA   

Other Uses
Research Purposes   
Alloys, In Nuclear Reactors, Nuclear Research, Research Purposes   

Biological Properties
  
  

Toxicity
Unknown   
Toxic   

Present in Human Body
No   
No   

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
Not Available   
2,150.00 °C   
10

Boiling Point
Not Available   
5,400.00 °C   
5

Appearance
  
  

Physical State
Solid   
Solid   

Color
Silver   
Gray   

Luster
Unknown Luster   
Metallic   

Hardness
  
  

Mohs Hardness
Not Available   
5.50   
7

Brinell Hardness
Not Available   
1,450.00 MPa   
6

Vickers Hardness
Not Available   
1,520.00 MPa   
5

Speed of Sound
Not Available   
3,010.00 m/s   
27

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
Rg   
Hf   

Isotopes
  
  

Known Isotopes
1   
34
32   
7

Electronegativity
  
  

Pauling Electronegativity
Not Available   
1.30   
32

Allred Rochow Electronegativity
Not Available   
1.23   
25

Allen Electronegativity
Not Available   
1.16   
37

Electropositivity
  
  

Pauling Electropositivity
Not Available   
2.70   
22

Ionization Energies
  
  

1st Energy Level
1,022.70 kJ/mol   
3
658.50 kJ/mol   
40

2nd Energy Level
2,074.40 kJ/mol   
10
1,440.00 kJ/mol   
99+

3rd Energy Level
3,077.90 kJ/mol   
24
2,250.00 kJ/mol   
99+

4th Energy Level
4,052.40 kJ/mol   
36
3,216.00 kJ/mol   
99+

5th Energy Level
5,306.70 kJ/mol   
31
Not Available   

Electrochemical Equivalent
Not Available   
1.66 g/amp-hr   
99+

Electron Work Function
Not Available   
3.90 eV   
27

Other Chemical Properties
NA   
Anti Corrosion, Ionization, Radioactive Isotopes, Solubility   

Atomic Properties

Atomic Number
111   
7
72   
99+

Electron Configuration
[Rn] 5f14 6d9 7s2   
[Xe] 4f14 5d2 6s2   

Crystal Structure
Body Centered Cubic (BCC)   
Hexagonal Close Packed (HCP)   

Crystal Lattice
BCC-Crystal-Structure-.jpg#100   
BCC-Crystal-Structure-.jpg#100   

Atom
  
  

Number of Protons
111   
7
72   
99+

Number of Neutrons
161   
3
106   
29

Number of Electrons
111   
7
72   
99+

Radius of an Atom
  
  

Atomic Radius
Not Available   
159.00 pm   
28

Covalent Radius
Not Available   
175.00 pm   
23

Van der Waals Radius
Not Available   
200.00 pm   
28

Atomic Weight
281.00 amu   
6
178.49 amu   
39

Atomic Volume
Not Available   
13.60 cm3/mol   
38

Adjacent Atomic Numbers
  
  

Previous Element
Lutetium
  

Next Element
Tantalum
  

Valence Electron Potential
Not Available   
81.00 (-eV)   
16

Lattice Constant
Not Available   
319.64 pm   
99+

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

Lattice C/A Ratio
Not Available   
1.58   
12

Mechanical Properties

Density
  
  

Density At Room Temperature
28.70 g/cm3   
6
13.31 g/cm3   
26

Density When Liquid (at m.p.)
Not Available   
12.00 g/cm3   
12

Tensile Strength
Not Available   
445.00 MPa   
8

Viscosity
Not Available   
Not Available   

Vapor Pressure
  
  

Vapor Pressure at 2000 K
Not Available   
0.00 (Pa)   
24

Elasticity properties
  
  

Shear Modulus
Not Available   
30.00 GPa   
23

Bulk Modulus
Not Available   
110.00 GPa   
15

Young's Modulus
Not Available   
78.00 GPa   
25

Poisson Ratio
Not Available   
0.37   
7

Other Mechanical Properties
Unknown   
Ductile, Malleable   

Magnetic Properties

Magnetic Characteristics
  
  

Specific Gravity
Not Available   
13.31   
18

Magnetic Ordering
Unknown   
Paramagnetic   

Electrical Properties
  
  

Electrical Property
Unknown   
Conductor   

Resistivity
Not Available   
331.00 nΩ·m   
14

Electrical Conductivity
Not Available   
0.03 106/cm Ω   
39

Electron Affinity
Not Available   
0.00 kJ/mol   
40

Thermal Properties

Specific Heat
Not Available   
0.14 J/(kg K)   
37

Molar Heat Capacity
Not Available   
25.73 J/mol·K   
36

Thermal Conductivity
Not Available   
23.00 W/m·K   
99+

Critical Temperature
Not Available   
Not Available   

Thermal Expansion
Not Available   
5.90 µm/(m·K)   
99+

Enthalpy
  
  

Enthalpy of Vaporization
Not Available   
661.10 kJ/mol   
5

Enthalpy of Fusion
Not Available   
25.10 kJ/mol   
8

Enthalpy of Atomization
Not Available   
703.00 kJ/mol   
5

Standard Molar Entropy
Not Available   
43.60 J/mol.K   
34

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