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Thorium vs Protactinium


Protactinium vs Thorium


Periodic Table

Symbol
Th   
Pa   

Group Number
0   
18
Not Available   

Period Number
7   
7   

Block
f block   
f block   

Element Family
Actinide   
Actinide   

CAS Number
7440326   
99+
7440133   
99+

Space Group Name
P63/mmc   
I4/mmm   

Space Group Number
194.00   
5
139.00   
8

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.
  
  • Protactinium metal has 29 isotopes.
  • Isotopes of Protactinium-231 used in nuclear weapon.
  

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

History
  
  

Who Discovered
Jöns Jakob Berzelius   
William Crookes   

Discovery
In 1829   
In 1900   

Abundance
  
  

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

Abundance In Sun
~0.0004 %   
9
~-9999 %   

Abundance In Meteorites
0.05 %   
11
Not Available   

Abundance In Earth's Crust
0.66 %   
7
0.00 %   
99+

Abundance In Oceans
0.00 %   
15
0.00 %   
99+

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.
  
  • Currently known uses of Protactinium metal are limited to research purpose only.
  

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

Medical Uses
Dentistry, Surgical Instruments Manufacturing   
NA   

Other Uses
Alloys, Jewellery, Sculptures, Statues   
NA   

Biological Properties
  
  

Toxicity
Non Toxic   
Highly Toxic   

Present in Human Body
Yes   
No   

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

In Bone
0.02 p.p.m.   
29
0.00 p.p.m.   
36

Physical Properties

Melting Point
1,750.00 °C   
17
1,568.00 °C   
21

Boiling Point
4,790.00 °C   
8
4,027.00 °C   
12

Appearance
  
  

Physical State
Solid   
Solid   

Color
Silver   
Silver   

Luster
NA   
Metallic   

Hardness
  
  

Mohs Hardness
3.00   
12
Not Available   

Brinell Hardness
390.00 MPa   
29
Not Available   

Vickers Hardness
295.00 MPa   
29
Not Available   

Speed of Sound
2,490.00 m/s   
36
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
Th   
Pa   

Isotopes
  
  

Known Isotopes
28   
11
27   
12

Electronegativity
  
  

Pauling Electronegativity
1.30   
32
1.50   
27

Allred Rochow Electronegativity
1.11   
29
1.14   
28

Electropositivity
  
  

Pauling Electropositivity
2.70   
22
2.50   
27

Ionization Energies
  
  

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

2nd Energy Level
1,110.00 kJ/mol   
99+
1,128.00 kJ/mol   
99+

3rd Energy Level
1,978.00 kJ/mol   
99+
1,814.00 kJ/mol   
99+

4th Energy Level
2,780.00 kJ/mol   
99+
2,991.00 kJ/mol   
99+

Electrochemical Equivalent
2.16 g/amp-hr   
24
1.72 g/amp-hr   
99+

Electron Work Function
3.41 eV   
32
Not Available   

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

Atomic Properties

Atomic Number
90   
28
91   
27

Electron Configuration
[Rn] 6d2 7s2   
[Rn] 5f2 6d1 7s2   

Crystal Structure
Face Centered Cubic (FCC)   
Tetragonal (TETR)   

Crystal Lattice
FCC-Crystal-Structure-of-Thorium.jpg#100   
TETR-Crystal-Structure-of-Protactinium.jpg#100   

Atom
  
  

Number of Protons
90   
28
91   
27

Number of Neutrons
142   
15
122   
21

Number of Electrons
90   
28
91   
27

Radius of an Atom
  
  

Atomic Radius
179.80 pm   
15
163.00 pm   
25

Covalent Radius
206.00 pm   
7
200.00 pm   
11

Van der Waals Radius
237.00 pm   
15
243.00 pm   
11

Atomic Weight
232.04 amu   
23
231.04 amu   
24

Atomic Volume
19.90 cm3/mol   
20
15.00 cm3/mol   
34

Adjacent Atomic Numbers
  
  

Previous Element
Actinium
  
Thorium
  

Next Element
Uranium
  

Valence Electron Potential
59.30 (-eV)   
23
92.00 (-eV)   
11

Lattice Constant
508.42 pm   
14
392.50 pm   
23

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

Lattice C/A Ratio
Not Available   
Not Available   

Mechanical Properties

Density
  
  

Density At Room Temperature
11.72 g/cm3   
32
15.37 g/cm3   
20

Tensile Strength
Not Available   
Not Available   

Viscosity
Not Available   
Not Available   

Vapor Pressure
  
  

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

Elasticity properties
  
  

Shear Modulus
31.00 GPa   
21
Not Available   

Bulk Modulus
54.00 GPa   
22
Not Available   

Young's Modulus
79.00 GPa   
24
Not Available   

Poisson Ratio
0.27   
20
Not Available   

Other Mechanical Properties
Ductile   
Unknown   

Magnetic Properties

Magnetic Characteristics
  
  

Specific Gravity
11.70   
23
15.37   
12

Magnetic Ordering
Paramagnetic   
Paramagnetic   

Electrical Properties
  
  

Electrical Property
Superconductor   
Conductor   

Resistivity
157.00 nΩ·m   
22
177.00 nΩ·m   
21

Electrical Conductivity
0.07 106/cm Ω   
31
0.05 106/cm Ω   
34

Thermal Properties

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

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

Thermal Conductivity
54.00 W/m·K   
28
47.00 W/m·K   
32

Critical Temperature
Not Available   
Not Available   

Thermal Expansion
11.00 µm/(m·K)   
36
9.90 µm/(m·K)   
40

Enthalpy
  
  

Enthalpy of Vaporization
429.00 kJ/mol   
15
Not Available   

Enthalpy of Fusion
15.48 kJ/mol   
19
12.34 kJ/mol   
28

Enthalpy of Atomization
468.60 kJ/mol   
15
Not Available   

Standard Molar Entropy
27.30 J/mol.K   
99+
198.10 J/mol.K   
1

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