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Cesium Fermium Comparison


Fermium Cesium comparison


Periodic Table

Symbol
Cs   
Fm   

Group Number
1   
17
Not Available   

Period Number
6   
7   

Block
s block   
f block   

Element Family
Alkali   
Actinide   

CAS Number
7440462   
40
7440724   
19

Space Group Name
Im_ 3m   
Not Available   

Space Group Number
229.00   
1
Not Available   

Facts

Interesting Facts
Not Available   
  • Fermium metal is highly radioactive in nature.
  • Fermium is synthetically produced metal.
  

Sources
Earth's crust, Found in Minerals, Mining, Ores of Minerals   
Bombarding Pu-239 with Neutrons   

History
  
  

Who Discovered
Robert Bunsen and Gustav Kirchhoff   
Lawrence Berkeley National Laboratory   

Discovery
In 1860   
In 1952   

Abundance
  
  

Abundance In Universe
8 * 10-8 %   
24
Not Available   

Abundance In Sun
~0.0000008 %   
20
~-9999 %   

Abundance In Meteorites
0.00 %   
38
Not Available   

Abundance In Earth's Crust
0.00 %   
35
Not Available   

Abundance In Oceans
0.00 %   
17
Not Available   

Abundance In Humans
0.00 %   
17
Not Available   

Uses

Uses & Benefits
  • The most common use of cesium metal is as a drilling fluid. It is also used in optical glass manufacturing.
  • In vacuum tubes and radiation monitor equipment this metal is used as a catalyst promoter.
  
  • Currently known uses of Fermium metal are limited to research purpose only.
  

Industrial Uses
Aerospace Industry, Automobile Industry, Electrical Industry, Electronic Industry   
NA   

Medical Uses
NA   
NA   

Other Uses
Alloys   
NA   

Biological Properties
  
  

Toxicity
Mildly Toxic   
Unknown   

Present in Human Body
Yes   
No   

In Blood
0.00 Blood/mg dm-3   
28
0.00 Blood/mg dm-3   
37

In Bone
0.05 p.p.m.   
26
0.00 p.p.m.   
36

Physical Properties

Melting Point
28.50 °C   
99+
1,527.00 °C   
26

Boiling Point
678.40 °C   
99+
Not Available   

Appearance
  
  

Physical State
Solid   
Solid   

Color
Silvery Gold   
Unknown   

Luster
NA   
Not Defined   

Hardness
  
  

Mohs Hardness
0.20   
25
Not Available   

Brinell Hardness
0.14 MPa   
99+
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
Cs   
Fm   

Isotopes
  
  

Known Isotopes
36   
3
18   
21

Electronegativity
  
  

Pauling Electronegativity
0.79   
99+
1.30   
32

Sanderson Electronegativity
0.22   
33
Not Available   

Allred Rochow Electronegativity
0.86   
99+
1.20   
27

Mulliken-Jaffe Electronegativity
0.62   
26
Not Available   

Allen Electronegativity
0.66   
99+
Not Available   

Electropositivity
  
  

Pauling Electropositivity
3.21   
2
2.70   
22

Ionization Energies
  
  

1st Energy Level
375.70 kJ/mol   
99+
627.00 kJ/mol   
99+

2nd Energy Level
2,234.30 kJ/mol   
8
1,225.00 kJ/mol   
99+

3rd Energy Level
3,400.00 kJ/mol   
16
2,363.00 kJ/mol   
99+

4th Energy Level
Not Available   
3,792.00 kJ/mol   
99+

Electrochemical Equivalent
4.96 g/amp-hr   
3
3.20 g/amp-hr   
13

Electron Work Function
2.14 eV   
99+
Not Available   

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

Atomic Properties

Atomic Number
55   
99+
100   
18

Electron Configuration
[Xe] 6s1   
[Rn] 5f12 7s2   

Crystal Structure
Body Centered Cubic (BCC)   
Not Known   

Crystal Lattice
BCC-Crystal-Structure-.jpg#100   
Unknown-Crystal-Structure-of-Fermium.jpg#100   

Atom
  
  

Number of Protons
55   
99+
100   
18

Number of Neutrons
78   
99+
157   
7

Number of Electrons
55   
99+
100   
18

Radius of an Atom
  
  

Atomic Radius
265.00 pm   
1
Not Available   

Covalent Radius
244.00 pm   
2
Not Available   

Van der Waals Radius
343.00 pm   
2
245.00 pm   
9

Atomic Weight
132.91 amu   
99+
257.00 amu   
15

Atomic Volume
71.07 cm3/mol   
1
Not Available   

Adjacent Atomic Numbers
  
  

Previous Element
Tin
  

Next Element
Barium
  

Valence Electron Potential
8.62 (-eV)   
99+
Not Available   

Lattice Constant
614.10 pm   
5
Not Available   

Lattice Angles
π/2, π/2, π/2   
NA   

Lattice C/A Ratio
Not Available   
Not Available   

Mechanical Properties

Density
  
  

Density At Room Temperature
1.93 g/cm3   
99+
Not Available   

Density When Liquid (at m.p.)
1.84 g/cm3   
99+
Not Available   

Tensile Strength
Not Available   
Not Available   

Viscosity
Not Available   
Not Available   

Vapor Pressure
  
  

Elasticity properties
  
  

Bulk Modulus
1.60 GPa   
99+
Not Available   

Young's Modulus
1.70 GPa   
99+
Not Available   

Poisson Ratio
Not Available   
Not Available   

Other Mechanical Properties
Ductile   
NA   

Magnetic Properties

Magnetic Characteristics
  
  

Specific Gravity
1.87   
99+
Not Available   

Magnetic Ordering
Paramagnetic   
Unknown   

Electrical Properties
  
  

Electrical Property
Semiconductor   
Unknown   

Resistivity
205.00 nΩ·m   
17
Not Available   

Electrical Conductivity
0.05 106/cm Ω   
35
Not Available   

Electron Affinity
45.50 kJ/mol   
25
Not Available   

Thermal Properties

Specific Heat
0.24 J/(kg K)   
23
Not Available   

Molar Heat Capacity
32.21 J/mol·K   
4
Not Available   

Thermal Conductivity
35.90 W/m·K   
36
Not Available   

Critical Temperature
1,938.00 K   
5
Not Available   

Thermal Expansion
97.00 µm/(m·K)   
1
Not Available   

Enthalpy
  
  

Enthalpy of Vaporization
65.90 kJ/mol   
99+
Not Available   

Enthalpy of Fusion
2.10 kJ/mol   
99+
Not Available   

Enthalpy of Atomization
78.20 kJ/mol   
99+
Not Available   

Standard Molar Entropy
85.20 J/mol.K   
3
Not Available   

Summary >>
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