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Promethium Thorium Comparison


Thorium Promethium comparison


Periodic Table

Symbol
Pm   
Th   

Group Number
Not Available   
0   
18

Period Number
6   
7   

Block
f block   
f block   

Element Family
Lanthanide   
Actinide   

CAS Number
7440122   
99+
7440326   
99+

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.
  
  • Thorium metal is used as an alternate option over Uranium for nuclear fuel.
  • Thorium metals appearance (silvery white, soft) is somewhat similar to Lead metal.
  

Sources
Found in Minerals, Mining   
Found in Minerals, Mining   

History
  
  

Who Discovered
Chien Shiung Wu, Emilio Segrè, Hans Bethe   
Jöns Jakob Berzelius   

Discovery
In 1942   
In 1829   

Abundance
  
  

Abundance In Universe
Not Available   
3 * 10-4 %   
9

Abundance In Sun
~-9999 %   
~0.0004 %   
9

Abundance In Meteorites
Not Available   
0.05 %   
11

Abundance In Earth's Crust
Not Available   
0.66 %   
7

Abundance In Oceans
Not Available   
0.00 %   
15

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.
  
  • Thorium metal is used as an allying agent for Magnesium, It imparts greater strength and resistance to temperature.
  • compound of this metal Thorium oxide is used as an industrial catalyst.
  

Industrial Uses
NA   
Aerospace Industry, Automobile Industry, Chemical Industry, Electrical Industry, Electronic Industry   

Medical Uses
NA   
Dentistry, Surgical Instruments Manufacturing   

Other Uses
NA   
Alloys, Jewellery, Sculptures, Statues   

Biological Properties
  
  

Toxicity
Non Toxic   
Non Toxic   

Present in Human Body
No   
Yes   

In Blood
0.00 Blood/mg dm-3   
37
0.00 Blood/mg dm-3   
33

In Bone
Not Available   
0.02 p.p.m.   
29

Physical Properties

Melting Point
1,042.00 °C   
99+
1,750.00 °C   
17

Boiling Point
3,000.00 °C   
31
4,790.00 °C   
8

Appearance
  
  

Physical State
Solid   
Solid   

Color
Unknown   
Silver   

Luster
Metallic   
NA   

Hardness
  
  

Mohs Hardness
Not Available   
3.00   
12

Brinell Hardness
Not Available   
390.00 MPa   
29

Vickers Hardness
Not Available   
295.00 MPa   
29

Speed of Sound
Not Available   
2,490.00 m/s   
36

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   
Th   

Isotopes
  
  

Known Isotopes
27   
12
28   
11

Electronegativity
  
  

Pauling Electronegativity
Not Available   
1.30   
32

Allred Rochow Electronegativity
1.07   
32
1.11   
29

Electropositivity
  
  

Pauling Electropositivity
Not Available   
2.70   
22

Ionization Energies
  
  

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

2nd Energy Level
1,050.00 kJ/mol   
99+
1,110.00 kJ/mol   
99+

3rd Energy Level
2,150.00 kJ/mol   
99+
1,978.00 kJ/mol   
99+

4th Energy Level
3,970.00 kJ/mol   
38
2,780.00 kJ/mol   
99+

Electrochemical Equivalent
1.80 g/amp-hr   
36
2.16 g/amp-hr   
24

Electron Work Function
Not Available   
3.41 eV   
32

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

Atomic Properties

Atomic Number
61   
99+
90   
28

Electron Configuration
[Xe] 4f5 6s2   
[Rn] 6d2 7s2   

Crystal Structure
Double Hexagonal Close Packed (DHCP)   
Face Centered Cubic (FCC)   

Crystal Lattice
DHCP-Crystal-Structure-of-Promethium.jpg#100   
FCC-Crystal-Structure-of-Thorium.jpg#100   

Atom
  
  

Number of Protons
61   
99+
90   
28

Number of Neutrons
84   
40
142   
15

Number of Electrons
61   
99+
90   
28

Radius of an Atom
  
  

Atomic Radius
183.00 pm   
10
179.80 pm   
15

Covalent Radius
199.00 pm   
12
206.00 pm   
7

Van der Waals Radius
236.00 pm   
16
237.00 pm   
15

Atomic Weight
145.00 amu   
99+
232.04 amu   
23

Atomic Volume
22.39 cm3/mol   
12
19.90 cm3/mol   
20

Adjacent Atomic Numbers
  
  

Previous Element
Neodymium
  
Actinium
  

Next Element
Samarium
  

Valence Electron Potential
44.10 (-eV)   
39
59.30 (-eV)   
23

Lattice Constant
Not Available   
508.42 pm   
14

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

Lattice C/A Ratio
Not Available   
Not Available   

Mechanical Properties

Density
  
  

Density At Room Temperature
7.26 g/cm3   
99+
11.72 g/cm3   
32

Tensile Strength
Not Available   
Not Available   

Viscosity
Not Available   
Not Available   

Vapor Pressure
  
  

Vapor Pressure at 2000 K
Not Available   
0.00 (Pa)   
22

Elasticity properties
  
  

Shear Modulus
18.00 GPa   
36
31.00 GPa   
21

Bulk Modulus
33.00 GPa   
36
54.00 GPa   
22

Young's Modulus
46.00 GPa   
38
79.00 GPa   
24

Poisson Ratio
0.28   
17
0.27   
20

Other Mechanical Properties
NA   
Ductile   

Magnetic Properties

Magnetic Characteristics
  
  

Specific Gravity
7.26   
99+
11.70   
23

Magnetic Ordering
Paramagnetic   
Paramagnetic   

Electrical Properties
  
  

Electrical Property
Conductor   
Superconductor   

Resistivity
0.75 nΩ·m   
99+
157.00 nΩ·m   
22

Electrical Conductivity
Not Available   
0.07 106/cm Ω   
31

Electron Affinity
50.00 kJ/mol   
21
Not Available   

Thermal Properties

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

Molar Heat Capacity
Not Available   
26.23 J/mol·K   
30

Thermal Conductivity
17.90 W/m·K   
99+
54.00 W/m·K   
28

Critical Temperature
Not Available   
Not Available   

Thermal Expansion
9.00 µm/(m·K)   
99+
11.00 µm/(m·K)   
36

Enthalpy
  
  

Enthalpy of Vaporization
Not Available   
429.00 kJ/mol   
15

Enthalpy of Fusion
7.50 kJ/mol   
99+
15.48 kJ/mol   
19

Enthalpy of Atomization
310.00 kJ/mol   
34
468.60 kJ/mol   
15

Standard Molar Entropy
Not Available   
27.30 J/mol.K   
99+

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