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Californium vs Francium


Francium vs Californium


Periodic Table

Symbol
Cf   
Fr   

Group Number
Not Available   
1   
17

Period Number
7   
7   

Block
f block   
s block   

Element Family
Actinide   
Alkali   

CAS Number
7440713   
20
7440735   
18

Space Group Name
P63/mmc   
Not Available   

Space Group Number
194.00   
5
Not Available   

Facts

Interesting Facts
  • Californium metal is very harmful and highly radioactive.
  • Californium metal is the heaviest metal.
  
  • 223 Francium has the longest half life at 21.8.
  • Francium metal is produced by alpha decay in 227Actinium 227.
  

Sources
Made by Bombarding Curium with Helium Ions   
Formed by Decay Process, Mining   

History
  
  

Who Discovered
Lawrence Berkeley National Laboratory   
Marguerite Perey   

Discovery
In 1950   
In 1939   

Abundance
  
  

Uses

Uses & Benefits
  • Californium metal has a very strong neutron emitter. It is used as a metal detector.
  • It also used as an identifier to check Water and oil layers in oil wells.
  
  • Francium has no known uses as it has a half life of only 22 minutes.
  

Industrial Uses
Chemical Industry   
NA   

Medical Uses
NA   
NA   

Other Uses
Alloys, Nuclear Research   
NA   

Biological Properties
  
  

Toxicity
Toxic   
NA   

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
900.00 °C   
99+
27.00 °C   
99+

Boiling Point
1,470.00 °C   
99+
677.00 °C   
99+

Appearance
  
  

Physical State
Solid   
Solid   

Color
Silver   
NA   

Luster
NA   
NA   

Hardness
  
  

Mohs Hardness
3.00   
12
Not Available   

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 Properties

Chemical Formula
Cf   
Fr   

Isotopes
  
  

Known Isotopes
20   
19
33   
6

Electronegativity
  
  

Pauling Electronegativity
1.30   
32
0.70   
99+

Allred Rochow Electronegativity
1.20   
27
0.86   
99+

Mulliken-Jaffe Electronegativity
Not Available   
0.68   
25

Allen Electronegativity
Not Available   
0.67   
99+

Electropositivity
  
  

Pauling Electropositivity
2.70   
22
3.30   
1

Ionization Energies
  
  

1st Energy Level
608.00 kJ/mol   
99+
380.00 kJ/mol   
99+

2nd Energy Level
1,206.00 kJ/mol   
99+
Not Available   

3rd Energy Level
2,267.00 kJ/mol   
99+
Not Available   

4th Energy Level
3,599.00 kJ/mol   
99+
Not Available   

Electrochemical Equivalent
3.12 g/amp-hr   
15
8.32 g/amp-hr   
1

Electron Work Function
Not Available   
Not Available   

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

Atomic Properties

Atomic Number
98   
20
87   
31

Electron Configuration
[Rn] 5f10 7s2   
[Rn] 7s1   

Crystal Structure
Double Hexagonal Close Packed (DHCP)   
Body Centered Cubic (BCC)   

Crystal Lattice
DHCP-Crystal-Structure-of-Californium.jpg#100   
BCC-Crystal-Structure-.jpg#100   

Atom
  
  

Number of Protons
98   
20
87   
31

Number of Neutrons
153   
9
136   
17

Number of Electrons
98   
20
87   
31

Radius of an Atom
  
  

Atomic Radius
186.00 pm   
9
Not Available   

Covalent Radius
Not Available   
260.00 pm   
1

Van der Waals Radius
Not Available   
348.00 pm   
1

Atomic Weight
251.00 amu   
17
223.00 amu   
27

Atomic Volume
Not Available   
Not Available   

Adjacent Atomic Numbers
  
  

Previous Element
Berkelium
  
Polonium
  

Next Element
Radium
  

Valence Electron Potential
44.50 (-eV)   
38
8.00 (-eV)   
99+

Lattice Constant
338.00 pm   
99+
Not Available   

Lattice Angles
π/2, π/2, 2 π/3   
NA   

Lattice C/A Ratio
Not Available   
Not Available   

Mechanical Properties

Density
  
  

Density At Room Temperature
15.10 g/cm3   
21
1.87 g/cm3   
99+

Tensile Strength
Not Available   
Not Available   

Viscosity
Not Available   
Not Available   

Vapor Pressure
  
  

Elasticity properties
  
  

Poisson Ratio
Not Available   
Not Available   

Other Mechanical Properties
Malleable, Sectile   
NA   

Magnetic Properties

Magnetic Characteristics
  
  

Specific Gravity
15.10   
13
Not Available   

Magnetic Ordering
Paramagnetic   
Paramagnetic   

Electrical Properties
  
  

Electrical Property
Unknown   
Poor Conductor   

Resistivity
Not Available   
3.00 nΩ·m   
99+

Electrical Conductivity
Not Available   
0.03 106/cm Ω   
40

Thermal Properties

Specific Heat
Not Available   
Not Available   

Molar Heat Capacity
Not Available   
Not Available   

Thermal Conductivity
Not Available   
15.00 W/m·K   
99+

Critical Temperature
Not Available   
Not Available   

Thermal Expansion
Not Available   
Not Available   

Enthalpy
  
  

Enthalpy of Atomization
Not Available   
71.00 kJ/mol   
99+

Standard Molar Entropy
Not Available   
Not Available   

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