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Neptunium vs Promethium


Promethium vs Neptunium


Periodic Table

Symbol
Np  
Pm  

Group Number
3  
15
3  
15

Period Number
7  
6  

Block
f block  
f block  

Element Family
Actinide  
Lanthanide  

CAS Number
7439998  
99+
7440122  
99+

Space Group Name
Pnma  
-  

Space Group Number
62.00  
14
194.00  
7

Facts

Interesting Facts
Neptunium was the first transuranium element to be discovered.  
  • 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
  
  

Abundance In Universe
0.00 %  
40
0.00 %  
40

Abundance In Sun
0.00 %  
26
-  

Abundance In Meteorites
0.00 %  
99+
-  

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

Abundance In Oceans
-  
-  

Abundance In Humans
0.00 %  
24
0.00 %  
24

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
-  
-  

Medical Uses
-  
-  

Other Uses
Alloys, Nuclear Research, Research Purposes  
-  

Biological Properties
  
  

Toxicity
Toxic  
Non Toxic  

Present in Human Body
No  
No  

In Blood
0.00 Blood/mg dm-3  
40
0.00 Blood/mg dm-3  
40

In Bone
0.00 p.p.m.  
99+
0.00 p.p.m.  
99+

Physical

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

Boiling Point
3,902.00 °C  
13
3,000.00 °C  
32

Appearance
  
  

Physical State
Solid  
Solid  

Color
Silver  
-  

Luster
Metallic  
Metallic  

Hardness
  
  

Mohs Hardness
6.00  
6
-  

Brinell Hardness
622.00 MPa  
23
400.00 MPa  
34

Vickers Hardness
640.00 MPa  
23
600.00 MPa  
28

Speed of Sound
2,260.00 m/s  
99+
2,260.00 m/s  
99+

Optical Properties
  
  

Refractive Index
1.30  
99+
1.70  
27

Reflectivity
64.00 %  
19
63.00 %  
20

Allotropes
No  
No  

α Allotropes
-  
-  

β Allotropes
-  
-  

γ Allotropes
-  
-  

Chemical

Chemical Formula
Np  
Pm  

Isotopes
  
  

Known Isotopes
20  
19
27  
12

Electronegativity
  
  

Pauling Electronegativity
1.36  
30
1.13  
99+

Sanderson Electronegativity
1.36  
23
1.13  
36

Allred Rochow Electronegativity
1.22  
27
1.07  
33

Mulliken-Jaffe Electronegativity
1.36  
31
1.13  
99+

Allen Electronegativity
1.36  
37
1.13  
99+

Electropositivity
  
  

Pauling Electropositivity
2.64  
25
2.20  
39

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  
99+

5th Energy Level
6,180.00 kJ/mol  
99+
5,400.00 kJ/mol  
99+

6th Energy Level
5,785.00 kJ/mol  
99+
5,400.00 kJ/mol  
99+

7th Energy level
6,040.00 kJ/mol  
99+
5,400.00 kJ/mol  
99+

8th Energy Level
6,040.00 kJ/mol  
99+
5,400.00 kJ/mol  
99+

9th Energy Level
6,180.00 kJ/mol  
99+
5,400.00 kJ/mol  
99+

10th Energy Level
6,180.00 kJ/mol  
99+
5,400.00 kJ/mol  
99+

11th Energy Level
6,180.00 kJ/mol  
99+
5,400.00 kJ/mol  
99+

12th Energy Level
61,800.00 kJ/mol  
13
5,400.00 kJ/mol  
99+

13th Energy Level
6,180.00 kJ/mol  
40
5,400.00 kJ/mol  
99+

14th Energy Level
6,180.00 kJ/mol  
29
5,400.00 kJ/mol  
99+

15th Energy Level
60,600.00 kJ/mol  
99+
54,000.00 kJ/mol  
99+

16th Energy Level
60,420.00 kJ/mol  
31
54,000.00 kJ/mol  
99+

17th Energy Level
604.00 kJ/mol  
99+
540.50 kJ/mol  
99+

18th Energy Level
6,040.00 kJ/mol  
99+
5,400.00 kJ/mol  
99+

19th Energy Level
604.50 kJ/mol  
99+
540.00 kJ/mol  
99+

20th Energy Level
604.00 kJ/mol  
99+
540.00 kJ/mol  
99+

21st Energy Level
6,040.00 kJ/mol  
17
540.00 kJ/mol  
99+

22nd Energy Level
604.00 kJ/mol  
40
540.00 kJ/mol  
99+

23rd Energy Level
6,040.00 kJ/mol  
18
540.00 kJ/mol  
99+

24th Energy Level
604.50 kJ/mol  
99+
540.00 kJ/mol  
99+

25th Energy Level
604.00 kJ/mol  
99+
540.00 kJ/mol  
99+

26th Energy Level
604.00 kJ/mol  
99+
540.00 kJ/mol  
99+

27th Energy Level
604.00 kJ/mol  
99+
540.00 kJ/mol  
99+

28th Energy Level
604.00 kJ/mol  
99+
540.00 kJ/mol  
99+

29th Energy Level
604.00 kJ/mol  
99+
540.00 kJ/mol  
99+

30th Energy Level
604.00 kJ/mol  
99+
540.00 kJ/mol  
99+

Electrochemical Equivalent
1.77 g/amp-hr  
99+
1.80 g/amp-hr  
40

Electron Work Function
4.90 eV  
12
5.30 eV  
5

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

Atomic

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  
15
84  
99+

Number of Electrons
93  
25
61  
99+

Radius of an Atom
  
  

Atomic Radius
155.00 pm  
32
183.00 pm  
12

Covalent Radius
190.00 pm  
18
199.00 pm  
12

Van der Waals Radius
221.00 pm  
27
236.00 pm  
20

Atomic Weight
237.00 amu  
22
145.00 amu  
99+

Atomic Volume
11.62 cm3/mol  
99+
22.39 cm3/mol  
21

Adjacent Atomic Numbers
  
  

Previous Element
Uranium
  
Neodymium
  

Next Element
Plutonium
  
Samarium
  

Valence Electron Potential
96.00 (-eV)  
9
44.10 (-eV)  
40

Lattice Constant
666.30 pm  
3
-  

Lattice Angles
π/2, π/2, π/2  
-  

Lattice C/A Ratio
1.43  
99+
1.63  
14

Mechanical

Density
  
  

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

Density When Liquid (at m.p.)
20.25 g/cm3  
10
7.26 g/cm3  
99+

Tensile Strength
125.00 MPa  
26
75.00 MPa  
30

Viscosity
0.00  
25
0.00  
25

Vapor Pressure
  
  

Vapor Pressure at 1000 K
0.00 (Pa)  
22
0.00 (Pa)  
37

Vapor Pressure at 2000 K
0.11 (Pa)  
17
0.00 (Pa)  
31

Elasticity properties
  
  

Shear Modulus
5.60 GPa  
99+
18.00 GPa  
99+

Bulk Modulus
180.00 GPa  
9
33.00 GPa  
99+

Young's Modulus
46.00 GPa  
99+
46.00 GPa  
99+

Poisson Ratio
0.26  
22
0.28  
17

Other Mechanical Properties
Ductile  
-  

Magnetic

Magnetic Characteristics
  
  

Specific Gravity
20.25  
15
7.26  
99+

Magnetic Ordering
Paramagnetic  
Paramagnetic  

Permeability
0.00 H/m  
6
0.00 H/m  
11

Susceptibility
0.00  
24
0.00  
25

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+
0.00 106/cm Ω  
99+

Electron Affinity
118.60 kJ/mol  
6
50.00 kJ/mol  
26

Thermal

Specific Heat
0.12 J/(kg K)  
99+
0.18 J/(kg K)  
34

Molar Heat Capacity
29.46 J/mol·K  
10
27.60 J/mol·K  
20

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

Critical Temperature
913.00 K  
99+
1,315.00 K  
99+

Thermal Expansion
13.30 µm/(m·K)  
35
9.00 µm/(m·K)  
99+

Enthalpy
  
  

Enthalpy of Vaporization
336.00 kJ/mol  
39
289.00 kJ/mol  
99+

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

Enthalpy of Atomization
275.30 kJ/mol  
99+
310.00 kJ/mol  
99+

Standard Molar Entropy
64.00 J/mol.K  
21
57.00 J/mol.K  
30

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