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Thorium Samarium Comparison


Samarium Thorium comparison


Periodic Table

Symbol
Th   
Sm   

Group Number
0   
18
Not Available   

Period Number
7   
6   

Block
f block   
f block   

Element Family
Actinide   
Lanthanide   

CAS Number
7440326   
99+
7440199   
99+

Space Group Name
P63/mmc   
R_ 3m   

Space Group Number
194.00   
5
166.00   
6

Facts

Interesting Facts
  • 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.
  
  • Samarium metals helps stimulating body metabolism.
  • Samarium metals was 1st observed by Jean Charles Galissard de Marignac in Dydimia in 1853.
  

Sources
Found in Minerals, Mining   
Found in Minerals, Mining, Ores of Minerals   

History
  
  

Who Discovered
Jöns Jakob Berzelius   
Lecoq de Boisbaudran   

Discovery
In 1829   
In 1879   

Abundance
  
  

Abundance In Universe
3 * 10-4 %   
9
5 * 10-7 %   
19

Abundance In Sun
~0.0004 %   
9
~0.0000001 %   
26

Abundance In Meteorites
0.05 %   
11
0.00 %   
37

Abundance In Earth's Crust
0.66 %   
7
0.00 %   
29

Abundance In Oceans
0.00 %   
15
0.00 %   
40

Uses

Uses & Benefits
  • 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.
  
  • Magnets of Samarium cobalt alloy are stronger than that of Iron and hence, they are used in microwave application.
  • Samarium metal also used in optical lasers and infrared absorbing glasses and as a neutron absorber.
  

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

Medical Uses
Dentistry, Surgical Instruments Manufacturing   
NA   

Other Uses
Alloys, Jewellery, Sculptures, Statues   
Alloys, In Nuclear Reactors   

Biological Properties
  
  

Toxicity
Non Toxic   
Slightly Toxic   

Present in Human Body
Yes   
Yes   

In Blood
0.00 Blood/mg dm-3   
33
0.01 Blood/mg dm-3   
22

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

Physical Properties

Melting Point
1,750.00 °C   
17
1,072.00 °C   
99+

Boiling Point
4,790.00 °C   
8
1,900.00 °C   
99+

Appearance
  
  

Physical State
Solid   
Solid   

Color
Silver   
Silvery White   

Luster
NA   
Lustrous   

Hardness
  
  

Mohs Hardness
3.00   
12
Not Available   

Brinell Hardness
390.00 MPa   
29
441.00 MPa   
27

Vickers Hardness
295.00 MPa   
29
412.00 MPa   
24

Speed of Sound
2,490.00 m/s   
36
2,130.00 m/s   
99+

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
Th   
Sm   

Isotopes
  
  

Known Isotopes
28   
11
30   
9

Electronegativity
  
  

Pauling Electronegativity
1.30   
32
1.17   
40

Allred Rochow Electronegativity
1.11   
29
1.07   
32

Electropositivity
  
  

Pauling Electropositivity
2.70   
22
2.83   
14

Ionization Energies
  
  

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

2nd Energy Level
1,110.00 kJ/mol   
99+
1,070.00 kJ/mol   
99+

3rd Energy Level
1,978.00 kJ/mol   
99+
2,260.00 kJ/mol   
99+

4th Energy Level
2,780.00 kJ/mol   
99+
3,990.00 kJ/mol   
37

Electrochemical Equivalent
2.16 g/amp-hr   
24
1.87 g/amp-hr   
34

Electron Work Function
3.41 eV   
32
2.70 eV   
99+

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

Atomic Properties

Atomic Number
90   
28
62   
99+

Electron Configuration
[Rn] 6d2 7s2   
[Xe] 4f6 6s2   

Crystal Structure
Face Centered Cubic (FCC)   
Rhombohedral (RHO)   

Crystal Lattice
FCC-Crystal-Structure-of-Thorium.jpg#100   
RHO-Crystal-Structure-of-Samarium.jpg#100   

Atom
  
  

Number of Protons
90   
28
62   
99+

Number of Neutrons
142   
15
88   
39

Number of Electrons
90   
28
62   
99+

Radius of an Atom
  
  

Atomic Radius
179.80 pm   
15
180.00 pm   
14

Covalent Radius
206.00 pm   
7
198.00 pm   
13

Van der Waals Radius
237.00 pm   
15
229.00 pm   
20

Atomic Weight
232.04 amu   
23
150.36 amu   
99+

Atomic Volume
19.90 cm3/mol   
20
19.95 cm3/mol   
19

Adjacent Atomic Numbers
  
  

Previous Element
Actinium
  
Promethium
  

Next Element
Europium
  

Valence Electron Potential
59.30 (-eV)   
23
44.80 (-eV)   
37

Lattice Constant
508.42 pm   
14
362.10 pm   
33

Lattice Angles
π/2, π/2, π/2   
π/2, π/2, 2 π/3   

Lattice C/A Ratio
Not Available   
Not Available   

Mechanical Properties

Density
  
  

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

Density When Liquid (at m.p.)
Not Available   
7.16 g/cm3   
32

Tensile Strength
Not Available   
Not Available   

Viscosity
Not Available   
Not Available   

Vapor Pressure
  
  

Vapor Pressure at 1000 K
Not Available   
0.94 (Pa)   
9

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

Elasticity properties
  
  

Shear Modulus
31.00 GPa   
21
19.50 GPa   
34

Bulk Modulus
54.00 GPa   
22
37.80 GPa   
35

Young's Modulus
79.00 GPa   
24
49.70 GPa   
37

Poisson Ratio
0.27   
20
0.27   
19

Other Mechanical Properties
Ductile   
NA   

Magnetic Properties

Magnetic Characteristics
  
  

Specific Gravity
11.70   
23
7.52   
99+

Magnetic Ordering
Paramagnetic   
Paramagnetic   

Electrical Properties
  
  

Electrical Property
Superconductor   
Conductor   

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

Electrical Conductivity
0.07 106/cm Ω   
31
0.01 106/cm Ω   
99+

Electron Affinity
Not Available   
50.00 kJ/mol   
21

Thermal Properties

Specific Heat
0.12 J/(kg K)   
40
0.20 J/(kg K)   
31

Molar Heat Capacity
26.23 J/mol·K   
30
29.54 J/mol·K   
7

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

Critical Temperature
Not Available   
Not Available   

Thermal Expansion
11.00 µm/(m·K)   
36
12.70 µm/(m·K)   
30

Enthalpy
  
  

Enthalpy of Vaporization
429.00 kJ/mol   
15
166.40 kJ/mol   
99+

Enthalpy of Fusion
15.48 kJ/mol   
19
8.62 kJ/mol   
40

Enthalpy of Atomization
468.60 kJ/mol   
15
209.00 kJ/mol   
99+

Standard Molar Entropy
27.30 J/mol.K   
99+
69.60 J/mol.K   
15

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