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Fermium vs Mendelevium


Mendelevium vs Fermium


Periodic Table

Symbol
Fm   
Md   

Group Number
Not Available   
Not Available   

Period Number
7   
7   

Block
f block   
f block   

Element Family
Actinide   
Actinide   

CAS Number
7440724   
19
7440111   
99+

Space Group Name
Not Available   
Not Available   

Space Group Number
Not Available   
Not Available   

Facts

Interesting Facts
  • Fermium metal is highly radioactive in nature.
  • Fermium is synthetically produced metal.
  
  • Mendelevium metal is synthetically produced metal.
  • Mendelevium metal has been produced in only trace amount.
  

Sources
Bombarding Pu-239 with Neutrons   
Bombarding Einsteinium with Helium Ions   

History
  
  

Who Discovered
Lawrence Berkeley National Laboratory   
Lawrence Berkeley National Laboratory   

Discovery
In 1952   
In 1955   

Abundance
  
  

Uses

Uses & Benefits
  • Currently known uses of Fermium metal are limited to research purpose only.
  
  • Currently known uses of Mendelevium metal are limited to research purpose only.
  

Industrial Uses
NA   
NA   

Medical Uses
NA   
NA   

Other Uses
NA   
NA   

Biological Properties
  
  

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
1,527.00 °C   
26
827.00 °C   
99+

Boiling Point
Not Available   
Not Available   

Appearance
  
  

Physical State
Solid   
Solid   

Luster
Not Defined   
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 Properties

Chemical Formula
Fm   
Md   

Isotopes
  
  

Known Isotopes
18   
21
16   
23

Electronegativity
  
  

Pauling Electronegativity
1.30   
32
1.30   
32

Allred Rochow Electronegativity
1.20   
27
1.20   
27

Electropositivity
  
  

Pauling Electropositivity
2.70   
22
2.70   
22

Ionization Energies
  
  

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

2nd Energy Level
1,225.00 kJ/mol   
99+
1,235.00 kJ/mol   
99+

3rd Energy Level
2,363.00 kJ/mol   
99+
2,470.00 kJ/mol   
99+

4th Energy Level
3,792.00 kJ/mol   
99+
3,840.00 kJ/mol   
99+

Electrochemical Equivalent
3.20 g/amp-hr   
13
3.21 g/amp-hr   
12

Electron Work Function
Not Available   
Not Available   

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

Atomic Properties

Atomic Number
100   
18
101   
17

Electron Configuration
[Rn] 5f12 7s2   
[Rn] 5f13 7s2   

Crystal Structure
Not Known   
Not Known   

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

Atom
  
  

Number of Protons
100   
18
101   
17

Number of Neutrons
157   
7
157   
7

Number of Electrons
100   
18
101   
17

Radius of an Atom
  
  

Van der Waals Radius
245.00 pm   
9
246.00 pm   
8

Atomic Weight
257.00 amu   
15
258.00 amu   
14

Atomic Volume
Not Available   
Not Available   

Adjacent Atomic Numbers
  
  

Previous Element
Fermium
  

Next Element
Nobelium
  

Valence Electron Potential
Not Available   
Not Available   

Lattice Constant
Not Available   
Not Available   

Lattice Angles
NA   
NA   

Lattice C/A Ratio
Not Available   
Not Available   

Mechanical Properties

Density
  
  

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 Properties

Magnetic Characteristics
  
  

Electrical Properties
  
  

Thermal Properties

Specific Heat
Not Available   
Not Available   

Molar Heat Capacity
Not Available   
Not Available   

Thermal Conductivity
Not Available   
Not Available   

Critical Temperature
Not Available   
Not Available   

Thermal Expansion
Not Available   
Not Available   

Enthalpy
  
  

Standard Molar Entropy
Not Available   
Not Available   

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