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Neodymium vs Promethium


Promethium vs Neodymium


Periodic Table

Symbol
-  
Pm  

Group Number
1  
17
3  
15

Period Number
6  
6  

Block
f block  
f block  

Element Family
Lanthanide  
Lanthanide  

CAS Number
7440008  
99+
7440122  
99+

Space Group Name
P63/mmc  
-  

Space Group Number
194.00  
7
194.00  
7

Facts

Interesting Facts
  • Neodymium is not found free in nature, hence it is not a native metal.
  • Neodymium metal found in minerals like Monazite and Bastnaesite.
  
  • Promethium metal found in Pitchblende.
  • Promethium metal is highly radioactive metal.
  

Sources
Found in Minerals, Mining  
Found in Minerals, Mining  

History
  
  

Who Discovered
Carl Auer von Welsbach  
Chien Shiung Wu, Emilio Segrè, Hans Bethe  

Discovery
In 1885  
In 1942  

Abundance
  
  

Abundance In Universe
0.00 %  
17
0.00 %  
40

Abundance In Sun
0.00 %  
24
-  

Abundance In Meteorites
0.00 %  
30
-  

Abundance In Earth's Crust
0.00 %  
20
0.00 %  
99+

Abundance In Oceans
0.00 %  
30
-  

Abundance In Humans
0.00 %  
24
0.00 %  
24

Uses

Uses & Benefits
  • Neodymium-Iron-boron alloy is used to make permanent magnets.
  • It is used in microphones, Mp3 player, loudspeakers, mobile phones, etc.
  
  • 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
Aerospace Industry, Electrical Industry, Electronic Industry  
-  

Medical Uses
-  
-  

Other Uses
Alloys  
-  

Biological Properties
  
  

Toxicity
Non Toxic  
Non Toxic  

Present in Human Body
No  
No  

In Blood
0.00 Blood/mg dm-3  
34
0.00 Blood/mg dm-3  
40

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

Physical

Melting Point
1,010.00 °C  
99+
1,042.00 °C  
99+

Boiling Point
3,127.00 °C  
29
3,000.00 °C  
32

Appearance
  
  

Physical State
Solid  
Solid  

Color
Silvery White  
-  

Luster
Metallic  
Metallic  

Hardness
  
  

Mohs Hardness
7.00  
3
-  

Brinell Hardness
265.00 MPa  
99+
400.00 MPa  
34

Vickers Hardness
345.00 MPa  
99+
600.00 MPa  
28

Speed of Sound
2,330.00 m/s  
99+
2,260.00 m/s  
99+

Optical Properties
  
  

Refractive Index
1.64  
30
1.70  
27

Reflectivity
80.00 %  
7
63.00 %  
20

Allotropes
No  
No  

α Allotropes
-  
-  

β Allotropes
-  
-  

γ Allotropes
-  
-  

Chemical

Chemical Formula
-  
Pm  

Isotopes
  
  

Known Isotopes
30  
9
27  
12

Electronegativity
  
  

Pauling Electronegativity
1.14  
99+
1.13  
99+

Sanderson Electronegativity
1.14  
35
1.13  
36

Allred Rochow Electronegativity
1.07  
33
1.07  
33

Mulliken-Jaffe Electronegativity
1.14  
99+
1.13  
99+

Allen Electronegativity
1.14  
99+
1.13  
99+

Electropositivity
  
  

Pauling Electropositivity
2.86  
13
2.20  
39

Ionization Energies
  
  

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

2nd Energy Level
1,040.00 kJ/mol  
99+
1,050.00 kJ/mol  
99+

3rd Energy Level
2,130.00 kJ/mol  
99+
2,150.00 kJ/mol  
99+

4th Energy Level
3,900.00 kJ/mol  
99+
3,970.00 kJ/mol  
99+

5th Energy Level
5,330.00 kJ/mol  
99+
5,400.00 kJ/mol  
99+

6th Energy Level
5,330.00 kJ/mol  
99+
5,400.00 kJ/mol  
99+

7th Energy level
5,331.00 kJ/mol  
99+
5,400.00 kJ/mol  
99+

8th Energy Level
5,360.00 kJ/mol  
99+
5,400.00 kJ/mol  
99+

9th Energy Level
5,330.00 kJ/mol  
99+
5,400.00 kJ/mol  
99+

10th Energy Level
5,330.00 kJ/mol  
99+
5,400.00 kJ/mol  
99+

11th Energy Level
5,330.00 kJ/mol  
99+
5,400.00 kJ/mol  
99+

12th Energy Level
5,330.00 kJ/mol  
99+
5,400.00 kJ/mol  
99+

13th Energy Level
5,330.00 kJ/mol  
99+
5,400.00 kJ/mol  
99+

14th Energy Level
533.10 kJ/mol  
99+
5,400.00 kJ/mol  
99+

15th Energy Level
53,300.00 kJ/mol  
99+
54,000.00 kJ/mol  
99+

16th Energy Level
533.10 kJ/mol  
99+
54,000.00 kJ/mol  
99+

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

18th Energy Level
5,331.00 kJ/mol  
99+
5,400.00 kJ/mol  
99+

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

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

21st Energy Level
533.10 kJ/mol  
99+
540.00 kJ/mol  
99+

22nd Energy Level
533.00 kJ/mol  
99+
540.00 kJ/mol  
99+

23rd Energy Level
5,331.00 kJ/mol  
27
540.00 kJ/mol  
99+

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

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

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

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

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

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

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

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

Electron Work Function
3.20 eV  
99+
5.30 eV  
5

Other Chemical Properties
Chemical Stability, Corrosion, Flammable, Ionization  
Ionization, Radioactive Isotopes, Solubility  

Atomic

Atomic Number
60  
99+
61  
99+

Electron Configuration
[Xe] 4f4 6s2  
[Xe] 4f5 6s2  

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

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

Atom
  
  

Number of Protons
60  
99+
61  
99+

Number of Neutrons
84  
99+
84  
99+

Number of Electrons
60  
99+
61  
99+

Radius of an Atom
  
  

Atomic Radius
181.00 pm  
15
183.00 pm  
12

Covalent Radius
201.00 pm  
10
199.00 pm  
12

Van der Waals Radius
229.00 pm  
25
236.00 pm  
20

Atomic Weight
144.24 amu  
99+
145.00 amu  
99+

Atomic Volume
20.60 cm3/mol  
28
22.39 cm3/mol  
21

Adjacent Atomic Numbers
  
  

Previous Element
Neodymium
  

Next Element
Samarium
  

Valence Electron Potential
43.40 (-eV)  
99+
44.10 (-eV)  
40

Lattice Constant
365.80 pm  
33
-  

Lattice Angles
π/2, π/2, 2 π/3  
-  

Lattice C/A Ratio
1.61  
18
1.63  
14

Mechanical

Density
  
  

Density At Room Temperature
7.01 g/cm3  
99+
7.26 g/cm3  
99+

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

Tensile Strength
345.00 MPa  
13
75.00 MPa  
30

Viscosity
0.00  
25
0.00  
25

Vapor Pressure
  
  

Vapor Pressure at 1000 K
0.00 (Pa)  
23
0.00 (Pa)  
37

Vapor Pressure at 2000 K
101.00 (Pa)  
2
0.00 (Pa)  
31

Elasticity properties
  
  

Shear Modulus
16.30 GPa  
99+
18.00 GPa  
99+

Bulk Modulus
31.80 GPa  
99+
33.00 GPa  
99+

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

Poisson Ratio
0.28  
16
0.28  
17

Other Mechanical Properties
-  
-  

Magnetic

Magnetic Characteristics
  
  

Specific Gravity
7.00  
99+
7.26  
99+

Magnetic Ordering
Paramagnetic  
Paramagnetic  

Permeability
0.00 H/m  
7
0.00 H/m  
11

Susceptibility
0.00  
9
0.00  
25

Electrical Properties
  
  

Electrical Property
-  
Conductor  

Resistivity
643.00 nΩ·m  
6
0.75 nΩ·m  
99+

Electrical Conductivity
0.02 106/cm Ω  
99+
0.00 106/cm Ω  
99+

Electron Affinity
50.00 kJ/mol  
26
50.00 kJ/mol  
26

Thermal

Specific Heat
0.19 J/(kg K)  
33
0.18 J/(kg K)  
34

Molar Heat Capacity
27.45 J/mol·K  
22
27.60 J/mol·K  
20

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

Critical Temperature
1,297.00 K  
99+
1,315.00 K  
99+

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

Enthalpy
  
  

Enthalpy of Vaporization
273.00 kJ/mol  
99+
289.00 kJ/mol  
99+

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

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

Standard Molar Entropy
71.50 J/mol.K  
13
57.00 J/mol.K  
30

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