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Promethium Hafnium Comparison


Hafnium Promethium comparison


Periodic Table

Symbol
Pm   
Hf   

Group Number
Not Available   
4   
14

Period Number
6   
6   

Block
f block   
d block   

Element Family
Lanthanide   
Transition Metal   

CAS Number
7440122   
99+
7440586   
30

Space Group Name
Not Available   
P63/mmc   

Space Group Number
Not Available   
194.00   
5

Facts

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

Sources
Found in Minerals, Mining   
By-product Zirconium Refining   

History
  
  

Who Discovered
Chien Shiung Wu, Emilio Segrè, Hans Bethe   
Dirk Coster and George de Hevesy   

Discovery
In 1942   
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
  • It is used for research purpose. Very small amount of this metal is used in atomic batteries.
  • Its radioactive decay is used for a phosphor to give off light. The light emitted is converted into electricity.
  
  • 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
NA   
Alloys, In Nuclear Reactors, Nuclear Research, Research Purposes   

Biological Properties
  
  

Toxicity
Non Toxic   
Toxic   

Present in Human Body
No   
No   

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

Physical Properties

Melting Point
1,042.00 °C   
99+
2,150.00 °C   
10

Boiling Point
3,000.00 °C   
31
5,400.00 °C   
5

Appearance
  
  

Physical State
Solid   
Solid   

Color
Unknown   
Gray   

Luster
Metallic   
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
Pm   
Hf   

Isotopes
  
  

Known Isotopes
27   
12
32   
7

Electronegativity
  
  

Pauling Electronegativity
Not Available   
1.30   
32

Allred Rochow Electronegativity
1.07   
32
1.23   
25

Allen Electronegativity
Not Available   
1.16   
37

Electropositivity
  
  

Pauling Electropositivity
Not Available   
2.70   
22

Ionization Energies
  
  

1st Energy Level
540.00 kJ/mol   
99+
658.50 kJ/mol   
40

2nd Energy Level
1,050.00 kJ/mol   
99+
1,440.00 kJ/mol   
99+

3rd Energy Level
2,150.00 kJ/mol   
99+
2,250.00 kJ/mol   
99+

4th Energy Level
3,970.00 kJ/mol   
38
3,216.00 kJ/mol   
99+

Electrochemical Equivalent
1.80 g/amp-hr   
36
1.66 g/amp-hr   
99+

Electron Work Function
Not Available   
3.90 eV   
27

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

Atomic Properties

Atomic Number
61   
99+
72   
99+

Electron Configuration
[Xe] 4f5 6s2   
[Xe] 4f14 5d2 6s2   

Crystal Structure
Double Hexagonal Close Packed (DHCP)   
Hexagonal Close Packed (HCP)   

Crystal Lattice
DHCP-Crystal-Structure-of-Promethium.jpg#100   
BCC-Crystal-Structure-.jpg#100   

Atom
  
  

Number of Protons
61   
99+
72   
99+

Number of Neutrons
84   
40
106   
29

Number of Electrons
61   
99+
72   
99+

Radius of an Atom
  
  

Atomic Radius
183.00 pm   
10
159.00 pm   
28

Covalent Radius
199.00 pm   
12
175.00 pm   
23

Van der Waals Radius
236.00 pm   
16
200.00 pm   
28

Atomic Weight
145.00 amu   
99+
178.49 amu   
39

Atomic Volume
22.39 cm3/mol   
12
13.60 cm3/mol   
38

Adjacent Atomic Numbers
  
  

Previous Element
Neodymium
  
Lutetium
  

Next Element
Samarium
  
Tantalum
  

Valence Electron Potential
44.10 (-eV)   
39
81.00 (-eV)   
16

Lattice Constant
Not Available   
319.64 pm   
99+

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

Lattice C/A Ratio
Not Available   
1.58   
12

Mechanical Properties

Density
  
  

Density At Room Temperature
7.26 g/cm3   
99+
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
18.00 GPa   
36
30.00 GPa   
23

Bulk Modulus
33.00 GPa   
36
110.00 GPa   
15

Young's Modulus
46.00 GPa   
38
78.00 GPa   
25

Poisson Ratio
0.28   
17
0.37   
7

Other Mechanical Properties
NA   
Ductile, Malleable   

Magnetic Properties

Magnetic Characteristics
  
  

Specific Gravity
7.26   
99+
13.31   
18

Magnetic Ordering
Paramagnetic   
Paramagnetic   

Electrical Properties
  
  

Electrical Property
Conductor   
Conductor   

Resistivity
0.75 nΩ·m   
99+
331.00 nΩ·m   
14

Electrical Conductivity
Not Available   
0.03 106/cm Ω   
39

Electron Affinity
50.00 kJ/mol   
21
0.00 kJ/mol   
40

Thermal Properties

Specific Heat
0.18 J/(kg K)   
33
0.14 J/(kg K)   
37

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

Thermal Conductivity
17.90 W/m·K   
99+
23.00 W/m·K   
99+

Critical Temperature
Not Available   
Not Available   

Thermal Expansion
9.00 µm/(m·K)   
99+
5.90 µm/(m·K)   
99+

Enthalpy
  
  

Enthalpy of Vaporization
Not Available   
661.10 kJ/mol   
5

Enthalpy of Fusion
7.50 kJ/mol   
99+
25.10 kJ/mol   
8

Enthalpy of Atomization
310.00 kJ/mol   
34
703.00 kJ/mol   
5

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

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