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Promethium Polonium Comparison


Polonium Promethium comparison


Periodic Table

Symbol
Pm   
Po   

Group Number
Not Available   
16   
2

Period Number
6   
6   

Block
f block   
p block   

Element Family
Lanthanide   
Post-​Transition   

CAS Number
7440122   
99+
7440086   
99+

Space Group Name
Not Available   
Pm-3m   

Space Group Number
Not Available   
221.00   
3

Facts

Interesting Facts
  • Promethium metal found in Pitchblende.
  • Promethium metal is highly radioactive metal.
  
  • 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 Minerals, Mining   
Mining, Ores of metals   

History
  
  

Who Discovered
Chien Shiung Wu, Emilio Segrè, Hans Bethe   
Pierre Curie and Marie Curie   

Discovery
In 1942   
In 1898   

Abundance
  
  

Abundance In Oceans
Not Available   
0.00 %   
99+

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.
  
  • 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
Non 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
Not Available   
0.00 p.p.m.   
36

Physical Properties

Melting Point
1,042.00 °C   
99+
254.00 °C   
99+

Boiling Point
3,000.00 °C   
31
962.00 °C   
99+

Appearance
  
  

Physical State
Solid   
Solid   

Color
Unknown   
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
Pm   
Po   

Isotopes
  
  

Known Isotopes
27   
12
29   
10

Electronegativity
  
  

Pauling Electronegativity
Not Available   
2.00   
7

Allred Rochow Electronegativity
1.07   
32
1.76   
2

Mulliken-Jaffe Electronegativity
Not Available   
2.48   
1

Allen Electronegativity
Not Available   
2.19   
2

Electropositivity
  
  

Pauling Electropositivity
Not Available   
2.00   
99+

Ionization Energies
  
  

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

2nd Energy Level
1,050.00 kJ/mol   
99+
Not Available   

3rd Energy Level
2,150.00 kJ/mol   
99+
Not Available   

4th Energy Level
3,970.00 kJ/mol   
38
Not Available   

Electrochemical Equivalent
1.80 g/amp-hr   
36
3.90 g/amp-hr   
8

Electron Work Function
Not Available   
Not Available   

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

Atomic Properties

Atomic Number
61   
99+
84   
32

Electron Configuration
[Xe] 4f5 6s2   
[Xe] 4f14 5d10 6s2 6p4   

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

Crystal Lattice
DHCP-Crystal-Structure-of-Promethium.jpg#100   
MON-Crystal-Structure-of-Polonium.jpg#100   

Atom
  
  

Number of Protons
61   
99+
84   
32

Number of Neutrons
84   
40
125   
19

Number of Electrons
61   
99+
84   
32

Radius of an Atom
  
  

Atomic Radius
183.00 pm   
10
168.00 pm   
23

Covalent Radius
199.00 pm   
12
140.00 pm   
99+

Van der Waals Radius
236.00 pm   
16
197.00 pm   
29

Atomic Weight
145.00 amu   
99+
209.00 amu   
28

Atomic Volume
22.39 cm3/mol   
12
22.23 cm3/mol   
13

Adjacent Atomic Numbers
  
  

Previous Element
Neodymium
  
Bismuth
  

Next Element
Samarium
  
Francium
  

Valence Electron Potential
44.10 (-eV)   
39
Not Available   

Lattice Constant
Not Available   
335.90 pm   
99+

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+
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
  
  

Shear Modulus
18.00 GPa   
36
Not Available   

Bulk Modulus
33.00 GPa   
36
Not Available   

Young's Modulus
46.00 GPa   
38
Not Available   

Poisson Ratio
0.28   
17
Not Available   

Other Mechanical Properties
NA   
NA   

Magnetic Properties

Magnetic Characteristics
  
  

Specific Gravity
7.26   
99+
9.32   
31

Magnetic Ordering
Paramagnetic   
Nonmagnetic   

Electrical Properties
  
  

Electrical Property
Conductor   
Conductor   

Resistivity
0.75 nΩ·m   
99+
0.40 nΩ·m   
99+

Electrical Conductivity
Not Available   
0.02 106/cm Ω   
99+

Electron Affinity
50.00 kJ/mol   
21
183.30 kJ/mol   
3

Thermal Properties

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

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

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

Critical Temperature
Not Available   
Not Available   

Thermal Expansion
9.00 µm/(m·K)   
99+
23.50 µm/(m·K)   
16

Enthalpy
  
  

Enthalpy of Vaporization
Not Available   
60.30 kJ/mol   
99+

Enthalpy of Fusion
7.50 kJ/mol   
99+
13.00 kJ/mol   
26

Enthalpy of Atomization
310.00 kJ/mol   
34
134.00 kJ/mol   
99+

Standard Molar Entropy
Not Available   
Not Available   

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