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Protactinium vs Polonium


Polonium vs Protactinium


Periodic Table

Symbol
Pa   
Po   

Group Number
Not Available   
16   
2

Period Number
7   
6   

Block
f block   
p block   

Element Family
Actinide   
Post-​Transition   

CAS Number
7440133   
99+
7440086   
99+

Space Group Name
I4/mmm   
Pm-3m   

Space Group Number
139.00   
8
221.00   
3

Facts

Interesting Facts
  • Protactinium metal has 29 isotopes.
  • Isotopes of Protactinium-231 used in nuclear weapon.
  
  • Polonium was the first radioactive element to be discovered.
  • Polonium element and its compounds are highly radioactive.
  • Its alloy with Beryllium provides source of neutrons.
  

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

History
  
  

Who Discovered
William Crookes   
Pierre Curie and Marie Curie   

Discovery
In 1900   
In 1898   

Abundance
  
  

Abundance In Earth's Crust
0.00 %   
99+
Not Available   

Abundance In Oceans
0.00 %   
99+
0.00 %   
99+

Uses

Uses & Benefits
  • Currently known uses of Protactinium metal are limited to research purpose only.
  
  • Polonium metal has different Allotropes, it is used in antistatic devices and for research purpose.
  • A 1 gram of Polonium can reach a temperature of 500°C, hence it is used as a heat source for space equipment.
  

Industrial Uses
NA   
Aerospace Industry, Ammunition Industry   

Medical Uses
NA   
NA   

Other Uses
NA   
Alloys   

Biological Properties
  
  

Toxicity
Highly Toxic   
Highly Toxic   

Present in Human Body
No   
No   

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

In Bone
0.00 p.p.m.   
36
0.00 p.p.m.   
36

Physical Properties

Melting Point
1,568.00 °C   
21
254.00 °C   
99+

Boiling Point
4,027.00 °C   
12
962.00 °C   
99+

Appearance
  
  

Physical State
Solid   
Solid   

Color
Silver   
Silver   

Luster
Metallic   
NA   

Hardness
  
  

Speed of Sound
Not Available   
Not Available   

Optical Properties
  
  

Allotropes
No   
Yes   

α Allotropes
Not Available   
α-polonium   

β Allotropes
Not Available   
β-polonium   

γ Allotropes
Not Available   
Not Available   

Chemical Properties

Chemical Formula
Pa   
Po   

Isotopes
  
  

Known Isotopes
27   
12
29   
10

Electronegativity
  
  

Pauling Electronegativity
1.50   
27
2.00   
7

Allred Rochow Electronegativity
1.14   
28
1.76   
2

Mulliken-Jaffe Electronegativity
Not Available   
2.48   
1

Allen Electronegativity
Not Available   
2.19   
2

Electropositivity
  
  

Pauling Electropositivity
2.50   
27
2.00   
99+

Ionization Energies
  
  

1st Energy Level
568.00 kJ/mol   
99+
812.10 kJ/mol   
14

2nd Energy Level
1,128.00 kJ/mol   
99+
Not Available   

3rd Energy Level
1,814.00 kJ/mol   
99+
Not Available   

4th Energy Level
2,991.00 kJ/mol   
99+
Not Available   

Electrochemical Equivalent
1.72 g/amp-hr   
99+
3.90 g/amp-hr   
8

Electron Work Function
Not Available   
Not Available   

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

Atomic Properties

Atomic Number
91   
27
84   
32

Electron Configuration
[Rn] 5f2 6d1 7s2   
[Xe] 4f14 5d10 6s2 6p4   

Crystal Structure
Tetragonal (TETR)   
Monoclinic (MON)   

Crystal Lattice
TETR-Crystal-Structure-of-Protactinium.jpg#100   
MON-Crystal-Structure-of-Polonium.jpg#100   

Atom
  
  

Number of Protons
91   
27
84   
32

Number of Neutrons
122   
21
125   
19

Number of Electrons
91   
27
84   
32

Radius of an Atom
  
  

Atomic Radius
163.00 pm   
25
168.00 pm   
23

Covalent Radius
200.00 pm   
11
140.00 pm   
99+

Van der Waals Radius
243.00 pm   
11
197.00 pm   
29

Atomic Weight
231.04 amu   
24
209.00 amu   
28

Atomic Volume
15.00 cm3/mol   
34
22.23 cm3/mol   
13

Adjacent Atomic Numbers
  
  

Previous Element
Thorium
  
Bismuth
  

Next Element
Uranium
  
Francium
  

Valence Electron Potential
92.00 (-eV)   
11
Not Available   

Lattice Constant
392.50 pm   
23
335.90 pm   
99+

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
15.37 g/cm3   
20
9.20 g/cm3   
99+

Density When Liquid (at m.p.)
Not Available   
9.40 g/cm3   
19

Tensile Strength
Not Available   
Not Available   

Viscosity
Not Available   
Not Available   

Vapor Pressure
  
  

Elasticity properties
  
  

Poisson Ratio
Not Available   
Not Available   

Other Mechanical Properties
Unknown   
NA   

Magnetic Properties

Magnetic Characteristics
  
  

Specific Gravity
15.37   
12
9.32   
31

Magnetic Ordering
Paramagnetic   
Nonmagnetic   

Electrical Properties
  
  

Electrical Property
Conductor   
Conductor   

Resistivity
177.00 nΩ·m   
21
0.40 nΩ·m   
99+

Electrical Conductivity
0.05 106/cm Ω   
34
0.02 106/cm Ω   
99+

Electron Affinity
Not Available   
183.30 kJ/mol   
3

Thermal Properties

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

Molar Heat Capacity
Not Available   
26.40 J/mol·K   
28

Thermal Conductivity
47.00 W/m·K   
32
20.00 W/m·K   
99+

Critical Temperature
Not Available   
Not Available   

Thermal Expansion
9.90 µm/(m·K)   
40
23.50 µm/(m·K)   
16

Enthalpy
  
  

Enthalpy of Vaporization
Not Available   
60.30 kJ/mol   
99+

Enthalpy of Fusion
12.34 kJ/mol   
28
13.00 kJ/mol   
26

Enthalpy of Atomization
Not Available   
134.00 kJ/mol   
99+

Standard Molar Entropy
198.10 J/mol.K   
1
Not Available   

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