Symbol
Ra
  
Pm
  
Group Number
Not Available
  
Period Number
7
  
6
  
Block
s block
  
f block
  
Element Family
Alkaline Earth
  
Lanthanide
  
Space Group Name
Im_ 3m
  
Not Available
  
Space Group Number
Not Available
  
Interesting Facts
- Radium metal is the heaviest metal of Alkaline earth metals column.
- Radium metal is highly radioactive and does not have any stable isotopes.
  
- Promethium metal found in Pitchblende.
- Promethium metal is highly radioactive metal.
  
Sources
Mining, Ores of metals
  
Found in Minerals, Mining
  
History
  
  
Who Discovered
Not Available
  
Chien Shiung Wu, Emilio Segrè, Hans Bethe
  
Discovery
In 1898
  
In 1942
  
Abundance
  
  
Abundance In Earth's Crust
Not Available
  
Abundance In Oceans
Not Available
  
Abundance In Humans
Not Available
  
Uses & Benefits
- It is a highly radioactive metal; and sometime Radium-223 is used to treat prostate cancer.
-
It is used in luminous paints.
  
- 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.
  
Industrial Uses
NA
  
NA
  
Medical Uses
Pharmaceutical Industry
  
NA
  
Other Uses
NA
  
NA
  
Biological Properties
  
  
Toxicity
Highly Toxic
  
Non Toxic
  
Present in Human Body
No
  
No
  
In Blood
Not Available
  
0.00 Blood/mg dm-3
  
37
Melting Point
1,042.00 °C
  
99+
Boiling Point
1,737.00 °C
  
99+
3,000.00 °C
  
31
Appearance
  
  
Physical State
Solid
  
Solid
  
Color
Silvery White
  
Unknown
  
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
Ra
  
Pm
  
Isotopes
  
  
Electronegativity
  
  
Pauling Electronegativity
Not Available
  
Allred Rochow Electronegativity
Mulliken-Jaffe Electronegativity
Not Available
  
Allen Electronegativity
Not Available
  
Electropositivity
  
  
Pauling Electropositivity
Not Available
  
Ionization Energies
  
  
1st Energy Level
509.30 kJ/mol
  
99+
540.00 kJ/mol
  
99+
2nd Energy Level
979.00 kJ/mol
  
99+
1,050.00 kJ/mol
  
99+
3rd Energy Level
Not Available
  
2,150.00 kJ/mol
  
99+
4th Energy Level
Not Available
  
3,970.00 kJ/mol
  
38
Electrochemical Equivalent
4.22 g/amp-hr
  
6
1.80 g/amp-hr
  
36
Electron Work Function
Not Available
  
Not Available
  
Other Chemical Properties
Ionization, Radioactive Isotopes, Radioactivity
  
Ionization, Radioactive Isotopes, Solubility
  
Electron Configuration
[Rn] 7s2
  
[Xe] 4f5 6s2
  
Crystal Structure
Body Centered Cubic (BCC)
  
Double Hexagonal Close Packed (DHCP)
  
Crystal Lattice
BCC-Crystal-Structure-.jpg#100
  
DHCP-Crystal-Structure-of-Promethium.jpg#100
  
Atom
  
  
Radius of an Atom
  
  
Atomic Radius
Not Available
  
Atomic Weight
145.00 amu
  
99+
Atomic Volume
45.20 cm3/mol
  
4
22.39 cm3/mol
  
12
Adjacent Atomic Numbers
  
  
Valence Electron Potential
20.10 (-eV)
  
99+
44.10 (-eV)
  
39
Lattice Constant
Not Available
  
Lattice Angles
π/2, π/2, π/2
  
Unknown
  
Lattice C/A Ratio
Not Available
  
Not Available
  
Density
  
  
Density At Room Temperature
5.50 g/cm3
  
99+
7.26 g/cm3
  
99+
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
  
NA
  
Magnetic Characteristics
  
  
Magnetic Ordering
Nonmagnetic
  
Paramagnetic
  
Electrical Properties
  
  
Electrical Property
NA
  
Conductor
  
Resistivity
100.00 nΩ·m
  
31
Electron Affinity
Not Available
  
50.00 kJ/mol
  
21
Specific Heat
0.12 J/(kg K)
  
40
0.18 J/(kg K)
  
33
Molar Heat Capacity
Not Available
  
Not Available
  
Thermal Conductivity
18.60 W/m·K
  
99+
17.90 W/m·K
  
99+
Critical Temperature
Not Available
  
Not Available
  
Thermal Expansion
Not Available
  
9.00 µm/(m·K)
  
99+
Enthalpy
  
  
Enthalpy of Fusion
Not Available
  
7.50 kJ/mol
  
99+
Enthalpy of Atomization
163.00 kJ/mol
  
99+
310.00 kJ/mol
  
34
Standard Molar Entropy
71.00 J/mol.K
  
14
Not Available