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Holmium vs Fermium


Fermium vs Holmium


Periodic Table

Symbol
Ho   
Fm   

Group Number
Not Available   
Not Available   

Period Number
6   
7   

Block
f block   
f block   

Element Family
Lanthanide   
Actinide   

CAS Number
7440600   
29
7440724   
19

Space Group Name
P63/mmc   
Not Available   

Space Group Number
194.00   
5
Not Available   

Facts

Interesting Facts
  • Holmium metal is very soft and malleable.
  • Holmium metal is well known for its corrosion resistivity.
  
  • Fermium metal is highly radioactive in nature.
  • Fermium is synthetically produced metal.
  

Sources
Found in Minerals, Mining, Ores of Minerals   
Bombarding Pu-239 with Neutrons   

History
  
  

Who Discovered
Marc Delafontaine   
Lawrence Berkeley National Laboratory   

Discovery
In 1878   
In 1952   

Abundance
  
  

Abundance In Universe
5 * 10-8 %   
27
Not Available   

Abundance In Meteorites
0.00 %   
99+
Not Available   

Abundance In Earth's Crust
0.00 %   
38
Not Available   

Abundance In Oceans
0.00 %   
99+
Not Available   

Uses

Uses & Benefits
  • Holmium metal has an ability to absorb neutrons, so this metal is used in nuclear reactors to keep the chain reactions of elements under control.
  • Alloys of Holmium are used to produce Magnet.
  
  • Currently known uses of Fermium metal are limited to research purpose only.
  

Industrial Uses
NA   
NA   

Medical Uses
NA   
NA   

Other Uses
Alloys, Nuclear Research   
NA   

Biological Properties
  
  

Toxicity
Low Toxic   
Unknown   

Present in Human Body
No   
No   

In Blood
Not Available   
0.00 Blood/mg dm-3   
37

In Bone
Not Available   
0.00 p.p.m.   
36

Physical Properties

Melting Point
1,461.00 °C   
30
1,527.00 °C   
26

Boiling Point
2,600.00 °C   
99+
Not Available   

Appearance
  
  

Physical State
Solid   
Solid   

Color
Silvery White   
Unknown   

Luster
Metallic   
Not Defined   

Hardness
  
  

Brinell Hardness
746.00 MPa   
13
Not Available   

Vickers Hardness
481.00 MPa   
23
Not Available   

Speed of Sound
2,760.00 m/s   
30
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
Ho   
Fm   

Isotopes
  
  

Known Isotopes
34   
5
18   
21

Electronegativity
  
  

Pauling Electronegativity
1.23   
37
1.30   
32

Allred Rochow Electronegativity
1.10   
30
1.20   
27

Electropositivity
  
  

Pauling Electropositivity
2.77   
17
2.70   
22

Ionization Energies
  
  

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

2nd Energy Level
1,140.00 kJ/mol   
99+
1,225.00 kJ/mol   
99+

3rd Energy Level
2,204.00 kJ/mol   
99+
2,363.00 kJ/mol   
99+

4th Energy Level
4,100.00 kJ/mol   
34
3,792.00 kJ/mol   
99+

Electrochemical Equivalent
2.02 g/amp-hr   
29
3.20 g/amp-hr   
13

Electron Work Function
Not Available   
Not Available   

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

Atomic Properties

Atomic Number
67   
99+
100   
18

Electron Configuration
[Xe] 4f11 6s2   
[Rn] 5f12 7s2   

Crystal Structure
Hexagonal Close Packed (HCP)   
Not Known   

Crystal Lattice
HCP-Crystal-Structure-of-Holmium.jpg#100   
Unknown-Crystal-Structure-of-Fermium.jpg#100   

Atom
  
  

Number of Protons
67   
99+
100   
18

Number of Neutrons
98   
34
157   
7

Number of Electrons
67   
99+
100   
18

Radius of an Atom
  
  

Atomic Radius
176.00 pm   
18
Not Available   

Covalent Radius
192.00 pm   
17
Not Available   

Van der Waals Radius
216.00 pm   
24
245.00 pm   
9

Atomic Weight
164.93 amu   
99+
257.00 amu   
15

Atomic Volume
18.70 cm3/mol   
24
Not Available   

Adjacent Atomic Numbers
  
  

Previous Element
Dysprosium
  

Next Element
Erbium
  

Valence Electron Potential
47.90 (-eV)   
31
Not Available   

Lattice Constant
357.73 pm   
38
Not Available   

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

Lattice C/A Ratio
1.57   
17
Not Available   

Mechanical Properties

Density
  
  

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

Density When Liquid (at m.p.)
8.34 g/cm3   
26
Not Available   

Tensile Strength
Not Available   
Not Available   

Viscosity
Not Available   
Not Available   

Vapor Pressure
  
  

Vapor Pressure at 1000 K
0.00 (Pa)   
16
Not Available   

Elasticity properties
  
  

Shear Modulus
26.30 GPa   
28
Not Available   

Bulk Modulus
40.20 GPa   
32
Not Available   

Young's Modulus
64.80 GPa   
31
Not Available   

Poisson Ratio
0.23   
29
Not Available   

Other Mechanical Properties
Ductile, Malleable, Sectile   
NA   

Magnetic Properties

Magnetic Characteristics
  
  

Specific Gravity
8.80   
35
Not Available   

Magnetic Ordering
Paramagnetic   
Unknown   

Electrical Properties
  
  

Electrical Property
Conductor   
Unknown   

Resistivity
814.00 nΩ·m   
4
Not Available   

Electrical Conductivity
0.01 106/cm Ω   
99+
Not Available   

Electron Affinity
50.00 kJ/mol   
21
Not Available   

Thermal Properties

Specific Heat
0.16 J/(kg K)   
35
Not Available   

Molar Heat Capacity
27.15 J/mol·K   
19
Not Available   

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

Critical Temperature
Not Available   
Not Available   

Thermal Expansion
11.20 µm/(m·K)   
35
Not Available   

Enthalpy
  
  

Enthalpy of Vaporization
241.00 kJ/mol   
38
Not Available   

Enthalpy of Fusion
11.76 kJ/mol   
29
Not Available   

Enthalpy of Atomization
301.00 kJ/mol   
36
Not Available   

Standard Molar Entropy
75.30 J/mol.K   
8
Not Available   

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