Symbol
Pm
  
Pa
  
Group Number
Not Available
  
Not Available
  
Period Number
6
  
7
  
Block
f block
  
f block
  
Element Family
Lanthanide
  
Actinide
  
Space Group Name
Not Available
  
I4/mmm
  
Space Group Number
Not Available
  
Interesting Facts
- Promethium metal found in Pitchblende.
- Promethium metal is highly radioactive 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
Chien Shiung Wu, Emilio Segrè, Hans Bethe
  
William Crookes
  
Discovery
In 1942
  
In 1900
  
Abundance
  
  
Abundance In Earth's Crust
Not Available
  
Abundance In Oceans
Not Available
  
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.
  
- Currently known uses of Protactinium metal are limited to research purpose only.
  
Industrial Uses
NA
  
NA
  
Medical Uses
NA
  
NA
  
Other Uses
NA
  
NA
  
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
Melting Point
1,042.00 °C
  
99+
1,568.00 °C
  
21
Boiling Point
3,000.00 °C
  
31
4,027.00 °C
  
12
Appearance
  
  
Physical State
Solid
  
Solid
  
Color
Unknown
  
Silver
  
Luster
Metallic
  
Metallic
  
Hardness
  
  
Speed of Sound
Not Available
  
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 Formula
Pm
  
Pa
  
Isotopes
  
  
Electronegativity
  
  
Pauling Electronegativity
Not Available
  
Allred Rochow Electronegativity
Electropositivity
  
  
Pauling Electropositivity
Not Available
  
Ionization Energies
  
  
1st Energy Level
540.00 kJ/mol
  
99+
568.00 kJ/mol
  
99+
2nd Energy Level
1,050.00 kJ/mol
  
99+
1,128.00 kJ/mol
  
99+
3rd Energy Level
2,150.00 kJ/mol
  
99+
1,814.00 kJ/mol
  
99+
4th Energy Level
3,970.00 kJ/mol
  
38
2,991.00 kJ/mol
  
99+
Electrochemical Equivalent
1.80 g/amp-hr
  
36
1.72 g/amp-hr
  
99+
Electron Work Function
Not Available
  
Not Available
  
Other Chemical Properties
Ionization, Radioactive Isotopes, Solubility
  
Ionization, Radioactive Isotopes, Radioactivity
  
Electron Configuration
[Xe] 4f5 6s2
  
[Rn] 5f2 6d1 7s2
  
Crystal Structure
Double Hexagonal Close Packed (DHCP)
  
Tetragonal (TETR)
  
Crystal Lattice
DHCP-Crystal-Structure-of-Promethium.jpg#100
  
TETR-Crystal-Structure-of-Protactinium.jpg#100
  
Atom
  
  
Radius of an Atom
  
  
Atomic Weight
145.00 amu
  
99+
Atomic Volume
22.39 cm3/mol
  
12
15.00 cm3/mol
  
34
Adjacent Atomic Numbers
  
  
Valence Electron Potential
44.10 (-eV)
  
39
92.00 (-eV)
  
11
Lattice Constant
Not Available
  
Lattice Angles
Unknown
  
π/2, π/2, π/2
  
Lattice C/A Ratio
Not Available
  
Not Available
  
Density
  
  
Density At Room Temperature
7.26 g/cm3
  
99+
15.37 g/cm3
  
20
Tensile Strength
Not Available
  
Not Available
  
Viscosity
Not Available
  
Not Available
  
Vapor Pressure
  
  
Elasticity properties
  
  
Shear Modulus
Not Available
  
Bulk Modulus
Not Available
  
Young's Modulus
Not Available
  
Poisson Ratio
Not Available
  
Other Mechanical Properties
NA
  
Unknown
  
Magnetic Characteristics
  
  
Magnetic Ordering
Paramagnetic
  
Paramagnetic
  
Electrical Properties
  
  
Electrical Property
Conductor
  
Conductor
  
Resistivity
177.00 nΩ·m
  
21
Electrical Conductivity
Not Available
  
0.05 10
6/cm Ω
  
34
Electron Affinity
50.00 kJ/mol
  
21
Not Available
  
Specific Heat
0.18 J/(kg K)
  
33
0.12 J/(kg K)
  
40
Molar Heat Capacity
Not Available
  
Not Available
  
Thermal Conductivity
17.90 W/m·K
  
99+
47.00 W/m·K
  
32
Critical Temperature
Not Available
  
Not Available
  
Thermal Expansion
9.00 µm/(m·K)
  
99+
9.90 µm/(m·K)
  
40
Enthalpy
  
  
Enthalpy of Fusion
7.50 kJ/mol
  
99+
12.34 kJ/mol
  
28
Enthalpy of Atomization
310.00 kJ/mol
  
34
Not Available
  
Standard Molar Entropy
Not Available
  
198.10 J/mol.K
  
1