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Hafnium vs Neptunium

Hafnium
Neptunium
Neptunium vs Hafnium


Periodic Table
Symbol
Hf   
Np   
Group Number
4   
14
Not Available   
Period Number
6   
7   
Block
d block   
f block   
Element Family
Transition Metal   
Actinide   
CAS Number
7440586   
30
7439998   
99+
Space Group Name
P63/mmc   
Pnma   
Space Group Number
194.00   
5
62.00   
11
Facts
Interesting Facts
  • Hafnium metal is highly reactive, hence not found free in nature.
  • Hafnium metal as predicated after Mendeleev finished his periodic table.
  
Not Available   
Sources
By-product Zirconium Refining   
Made by Bombarding Uranium with Neutrons, Ores of metals   
History
  
  
Who Discovered
Dirk Coster and George de Hevesy   
Edwin McMillan and Philip H. Abelson   
Discovery
In 1922   
In 1940   
Abundance
  
  
Abundance In Universe
7 * 10-8 %   
25
Not Available   
Abundance In Sun
~0.0000001 %   
26
~-9999 %   
Abundance In Meteorites
0.00 %   
37
Not Available   
Abundance In Earth's Crust
0.00 %   
31
Not Available   
Abundance In Oceans
0.00 %   
27
Not Available   
Uses
Uses & Benefits
  • 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.
  
  • Currently known uses of Neptunium metal are limited to research purpose only.
  • Neptunium’s isotope neptunium-237 is used as a neutron detectors.
  
Industrial Uses
Ammunition Industry   
NA   
Medical Uses
NA   
NA   
Other Uses
Alloys, In Nuclear Reactors, Nuclear Research, Research Purposes   
Alloys, Nuclear Research, Research Purposes   
Biological Properties
  
  
Toxicity
Toxic   
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
2,150.00 °C   
10
640.00 °C   
99+
Boiling Point
5,400.00 °C   
5
3,902.00 °C   
13
Appearance
  
  
Physical State
Solid   
Solid   
Color
Gray   
Silver   
Luster
Metallic   
Metallic   
Hardness
  
  
Mohs Hardness
5.50   
7
Not Available   
Brinell Hardness
1,450.00 MPa   
6
Not Available   
Vickers Hardness
1,520.00 MPa   
5
Not Available   
Speed of Sound
3,010.00 m/s   
27
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
Hf   
Np   
Isotopes
  
  
Known Isotopes
32   
7
20   
19
Electronegativity
  
  
Pauling Electronegativity
1.30   
32
1.36   
29
Allred Rochow Electronegativity
1.23   
25
1.22   
26
Allen Electronegativity
1.16   
37
Not Available   
Electropositivity
  
  
Pauling Electropositivity
2.70   
22
2.64   
25
Ionization Energies
  
  
1st Energy Level
658.50 kJ/mol   
40
604.50 kJ/mol   
99+
2nd Energy Level
1,440.00 kJ/mol   
99+
1,128.00 kJ/mol   
99+
3rd Energy Level
2,250.00 kJ/mol   
99+
1,997.00 kJ/mol   
99+
4th Energy Level
3,216.00 kJ/mol   
99+
3,242.00 kJ/mol   
99+
Electrochemical Equivalent
1.66 g/amp-hr   
99+
1.77 g/amp-hr   
39
Electron Work Function
3.90 eV   
27
Not Available   
Other Chemical Properties
Anti Corrosion, Ionization, Radioactive Isotopes, Solubility   
Ionization, Radioactive Isotopes, Radioactivity, Solubility   
Atomic Properties
Atomic Number
72   
99+
93   
25
Electron Configuration
[Xe] 4f14 5d2 6s2   
[Rn] 5f4 6d1 7s2   
Crystal Structure
Hexagonal Close Packed (HCP)   
Orthorhombic (ORTH)   
Crystal Lattice
BCC-Crystal-Structure-.jpg#100   
ORTH-Crystal-Structure-of-Neptunium.jpg#100   
Atom
  
  
Number of Protons
72   
99+
93   
25
Number of Neutrons
106   
29
144   
14
Number of Electrons
72   
99+
93   
25
Radius of an Atom
  
  
Atomic Radius
159.00 pm   
28
155.00 pm   
30
Covalent Radius
175.00 pm   
23
190.00 pm   
18
Van der Waals Radius
200.00 pm   
28
221.00 pm   
22
Atomic Weight
178.49 amu   
39
237.00 amu   
22
Atomic Volume
13.60 cm3/mol   
38
11.62 cm3/mol   
99+
Adjacent Atomic Numbers
  
  
Previous Element
Lutetium
  
Uranium
  
Next Element
Tantalum
  
Plutonium
  
Valence Electron Potential
81.00 (-eV)   
16
96.00 (-eV)   
9
Lattice Constant
319.64 pm   
99+
666.30 pm   
3
Lattice Angles
π/2, π/2, 2 π/3   
π/2, π/2, π/2   
Lattice C/A Ratio
1.58   
12
Not Available   
Mechanical Properties
Density
  
  
Density At Room Temperature
13.31 g/cm3   
26
19.38 g/cm3   
14
Density When Liquid (at m.p.)
12.00 g/cm3   
12
Not Available   
Tensile Strength
445.00 MPa   
8
125.00 MPa   
14
Viscosity
Not Available   
Not Available   
Vapor Pressure
  
  
Vapor Pressure at 2000 K
0.00 (Pa)   
24
0.11 (Pa)   
17
Elasticity properties
  
  
Shear Modulus
30.00 GPa   
23
Not Available   
Bulk Modulus
110.00 GPa   
15
Not Available   
Young's Modulus
78.00 GPa   
25
Not Available   
Poisson Ratio
0.37   
7
Not Available   
Other Mechanical Properties
Ductile, Malleable   
Ductile   
Magnetic Properties
Magnetic Characteristics
  
  
Specific Gravity
13.31   
18
20.25   
6
Magnetic Ordering
Paramagnetic   
Paramagnetic   
Electrical Properties
  
  
Electrical Property
Conductor   
Conductor   
Resistivity
331.00 nΩ·m   
14
1.22 nΩ·m   
99+
Electrical Conductivity
0.03 106/cm Ω   
39
0.01 106/cm Ω   
99+
Electron Affinity
0.00 kJ/mol   
40
Not Available   
Thermal Properties
Specific Heat
0.14 J/(kg K)   
37
0.12 J/(kg K)   
40
Molar Heat Capacity
25.73 J/mol·K   
36
29.46 J/mol·K   
8
Thermal Conductivity
23.00 W/m·K   
99+
6.30 W/m·K   
99+
Critical Temperature
Not Available   
Not Available   
Thermal Expansion
5.90 µm/(m·K)   
99+
Not Available   
Enthalpy
  
  
Enthalpy of Vaporization
661.10 kJ/mol   
5
Not Available   
Enthalpy of Fusion
25.10 kJ/mol   
8
3.20 kJ/mol   
99+
Enthalpy of Atomization
703.00 kJ/mol   
5
Not Available   
Standard Molar Entropy
43.60 J/mol.K   
34
Not Available   
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