Symbol
Fr
  
Ds
  
Period Number
7
  
7
  
Block
s block
  
d block
  
Element Family
Alkali
  
Probably Transition
  
Space Group Name
Not Available
  
Not Available
  
Space Group Number
Not Available
  
Not Available
  
Interesting Facts
- 223 Francium has the longest half life at 21.8.
- Francium metal is produced by alpha decay in 227Actinium 227.
  
Not Available
  
Sources
Formed by Decay Process, Mining
  
Synthetically Produced
  
History
  
  
Who Discovered
Marguerite Perey
  
Gesellschaft für Schwerionenforschung
  
Discovery
In 1939
  
In 1994
  
Abundance
  
  
Uses & Benefits
- Francium has no known uses as it has a half life of only 22 minutes.
  
- Currently known uses of Darmstadtium metal are limited to research purpose only. As only few atoms of this metal are produced.
  
Industrial Uses
NA
  
NA
  
Medical Uses
NA
  
NA
  
Other Uses
NA
  
Research Purposes
  
Biological Properties
  
  
Toxicity
NA
  
Unknown
  
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
Melting Point
Not Available
  
Boiling Point
Not Available
  
Appearance
  
  
Physical State
Solid
  
Solid
  
Color
NA
  
Unknown
  
Luster
NA
  
Unknown Luster
  
Hardness
  
  
Speed of Sound
Not Available
  
5,090.00 m/s
  
9
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
Fr
  
Ds
  
Isotopes
  
  
Electronegativity
  
  
Pauling Electronegativity
Not Available
  
Allred Rochow Electronegativity
Not Available
  
Mulliken-Jaffe Electronegativity
Not Available
  
Allen Electronegativity
Not Available
  
Electropositivity
  
  
Pauling Electropositivity
Not Available
  
Ionization Energies
  
  
1st Energy Level
380.00 kJ/mol
  
99+
955.20 kJ/mol
  
5
2nd Energy Level
Not Available
  
1,891.10 kJ/mol
  
16
3rd Energy Level
Not Available
  
3,029.60 kJ/mol
  
25
4th Energy Level
Not Available
  
3,955.90 kJ/mol
  
40
5th Energy Level
Not Available
  
5,113.70 kJ/mol
  
33
Electrochemical Equivalent
8.32 g/amp-hr
  
1
Not Available
  
Electron Work Function
Not Available
  
Not Available
  
Other Chemical Properties
Ionization, Radioactive Isotopes, Radioactivity, Solubility
  
Ionization, Radioactive Isotopes, Radioactivity
  
Electron Configuration
[Rn] 7s1
  
[Rn] 5f14 6d8 7s2
  
Crystal Structure
Body Centered Cubic (BCC)
  
Body Centered Cubic (BCC)
  
Crystal Lattice
BCC-Crystal-Structure-.jpg#100
  
BCC-Crystal-Structure-.jpg#100
  
Atom
  
  
Radius of an Atom
  
  
Atomic Radius
Not Available
  
Van der Waals Radius
Not Available
  
Atomic Volume
Not Available
  
Not Available
  
Adjacent Atomic Numbers
  
  
Valence Electron Potential
8.00 (-eV)
  
99+
Not Available
  
Lattice Constant
Not Available
  
Not Available
  
Lattice Angles
NA
  
NA
  
Lattice C/A Ratio
Not Available
  
Not Available
  
Density
  
  
Density At Room Temperature
1.87 g/cm
3
  
99+
Not Available
  
Tensile Strength
Not Available
  
Not Available
  
Viscosity
Not Available
  
Not Available
  
Vapor Pressure
  
  
Elasticity properties
  
  
Poisson Ratio
Not Available
  
Not Available
  
Other Mechanical Properties
NA
  
Unknown
  
Magnetic Characteristics
  
  
Magnetic Ordering
Paramagnetic
  
Unknown
  
Electrical Properties
  
  
Electrical Property
Poor Conductor
  
Unknown
  
Resistivity
Not Available
  
Electrical Conductivity
0.03 10
6/cm Ω
  
40
Not Available
  
Specific Heat
Not Available
  
Not Available
  
Molar Heat Capacity
Not Available
  
Not Available
  
Thermal Conductivity
15.00 W/m·K
  
99+
Not Available
  
Critical Temperature
Not Available
  
Not Available
  
Thermal Expansion
Not Available
  
Not Available
  
Enthalpy
  
  
Enthalpy of Atomization
71.00 kJ/mol
  
99+
Not Available
  
Standard Molar Entropy
Not Available
  
Not Available