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Neptunium Promethium Comparison


Promethium Neptunium comparison


Periodic Table

Symbol
Np   
Pm   

Group Number
Not Available   
Not Available   

Period Number
7   
6   

Block
f block   
f block   

Element Family
Actinide   
Lanthanide   

CAS Number
7439998   
99+
7440122   
99+

Space Group Name
Pnma   
Not Available   

Space Group Number
62.00   
11
Not Available   

Facts

Interesting Facts
Not Available   
  • Promethium metal found in Pitchblende.
  • Promethium metal is highly radioactive metal.
  

Sources
Made by Bombarding Uranium with Neutrons, Ores of metals   
Found in Minerals, Mining   

History
  
  

Who Discovered
Edwin McMillan and Philip H. Abelson   
Chien Shiung Wu, Emilio Segrè, Hans Bethe   

Discovery
In 1940   
In 1942   

Abundance
  
  

Uses

Uses & Benefits
  • Currently known uses of Neptunium metal are limited to research purpose only.
  • Neptunium’s isotope neptunium-237 is used as a neutron detectors.
  
  • 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.
  

Industrial Uses
NA   
NA   

Medical Uses
NA   
NA   

Other Uses
Alloys, Nuclear Research, Research Purposes   
NA   

Biological Properties
  
  

Toxicity
Toxic   
Non Toxic   

Present in Human Body
No   
No   

In Blood
0.00 Blood/mg dm-3   
37
0.00 Blood/mg dm-3   
37

In Bone
0.00 p.p.m.   
36
Not Available   

Physical Properties

Melting Point
640.00 °C   
99+
1,042.00 °C   
99+

Boiling Point
3,902.00 °C   
13
3,000.00 °C   
31

Appearance
  
  

Physical State
Solid   
Solid   

Color
Silver   
Unknown   

Luster
Metallic   
Metallic   

Hardness
  
  

Speed of Sound
Not Available   
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
Np   
Pm   

Isotopes
  
  

Known Isotopes
20   
19
27   
12

Electronegativity
  
  

Pauling Electronegativity
1.36   
29
Not Available   

Allred Rochow Electronegativity
1.22   
26
1.07   
32

Electropositivity
  
  

Pauling Electropositivity
2.64   
25
Not Available   

Ionization Energies
  
  

1st Energy Level
604.50 kJ/mol   
99+
540.00 kJ/mol   
99+

2nd Energy Level
1,128.00 kJ/mol   
99+
1,050.00 kJ/mol   
99+

3rd Energy Level
1,997.00 kJ/mol   
99+
2,150.00 kJ/mol   
99+

4th Energy Level
3,242.00 kJ/mol   
99+
3,970.00 kJ/mol   
38

Electrochemical Equivalent
1.77 g/amp-hr   
39
1.80 g/amp-hr   
36

Electron Work Function
Not Available   
Not Available   

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

Atomic Properties

Atomic Number
93   
25
61   
99+

Electron Configuration
[Rn] 5f4 6d1 7s2   
[Xe] 4f5 6s2   

Crystal Structure
Orthorhombic (ORTH)   
Double Hexagonal Close Packed (DHCP)   

Crystal Lattice
ORTH-Crystal-Structure-of-Neptunium.jpg#100   
DHCP-Crystal-Structure-of-Promethium.jpg#100   

Atom
  
  

Number of Protons
93   
25
61   
99+

Number of Neutrons
144   
14
84   
40

Number of Electrons
93   
25
61   
99+

Radius of an Atom
  
  

Atomic Radius
155.00 pm   
30
183.00 pm   
10

Covalent Radius
190.00 pm   
18
199.00 pm   
12

Van der Waals Radius
221.00 pm   
22
236.00 pm   
16

Atomic Weight
237.00 amu   
22
145.00 amu   
99+

Atomic Volume
11.62 cm3/mol   
99+
22.39 cm3/mol   
12

Adjacent Atomic Numbers
  
  

Previous Element
Uranium
  
Neodymium
  

Next Element
Plutonium
  
Samarium
  

Valence Electron Potential
96.00 (-eV)   
9
44.10 (-eV)   
39

Lattice Constant
666.30 pm   
3
Not Available   

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

Lattice C/A Ratio
Not Available   
Not Available   

Mechanical Properties

Density
  
  

Density At Room Temperature
19.38 g/cm3   
14
7.26 g/cm3   
99+

Tensile Strength
125.00 MPa   
14
Not Available   

Viscosity
Not Available   
Not Available   

Vapor Pressure
  
  

Vapor Pressure at 2000 K
0.11 (Pa)   
17
Not Available   

Elasticity properties
  
  

Shear Modulus
Not Available   
18.00 GPa   
36

Bulk Modulus
Not Available   
33.00 GPa   
36

Young's Modulus
Not Available   
46.00 GPa   
38

Poisson Ratio
Not Available   
0.28   
17

Other Mechanical Properties
Ductile   
NA   

Magnetic Properties

Magnetic Characteristics
  
  

Specific Gravity
20.25   
6
7.26   
99+

Magnetic Ordering
Paramagnetic   
Paramagnetic   

Electrical Properties
  
  

Electrical Property
Conductor   
Conductor   

Resistivity
1.22 nΩ·m   
99+
0.75 nΩ·m   
99+

Electrical Conductivity
0.01 106/cm Ω   
99+
Not Available   

Electron Affinity
Not Available   
50.00 kJ/mol   
21

Thermal Properties

Specific Heat
0.12 J/(kg K)   
40
0.18 J/(kg K)   
33

Molar Heat Capacity
29.46 J/mol·K   
8
Not Available   

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

Critical Temperature
Not Available   
Not Available   

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

Enthalpy
  
  

Enthalpy of Fusion
3.20 kJ/mol   
99+
7.50 kJ/mol   
99+

Enthalpy of Atomization
Not Available   
310.00 kJ/mol   
34

Standard Molar Entropy
Not Available   
Not Available   

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