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Holmium Neptunium Comparison


Neptunium Holmium comparison


Periodic Table

Symbol
Ho   
Np   

Group Number
Not Available   
Not Available   

Period Number
6   
7   

Block
f block   
f block   

Element Family
Lanthanide   
Actinide   

CAS Number
7440600   
29
7439998   
99+

Space Group Name
P63/mmc   
Pnma   

Space Group Number
194.00   
5
62.00   
11

Facts

Interesting Facts
  • Holmium metal is very soft and malleable.
  • Holmium metal is well known for its corrosion resistivity.
  
Not Available   

Sources
Found in Minerals, Mining, Ores of Minerals   
Made by Bombarding Uranium with Neutrons, Ores of metals   

History
  
  

Who Discovered
Marc Delafontaine   
Edwin McMillan and Philip H. Abelson   

Discovery
In 1878   
In 1940   

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 Neptunium metal are limited to research purpose only.
  • Neptunium’s isotope neptunium-237 is used as a neutron detectors.
  

Industrial Uses
NA   
NA   

Medical Uses
NA   
NA   

Other Uses
Alloys, Nuclear Research   
Alloys, Nuclear Research, Research Purposes   

Biological Properties
  
  

Toxicity
Low Toxic   
Toxic   

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
640.00 °C   
99+

Boiling Point
2,600.00 °C   
99+
3,902.00 °C   
13

Appearance
  
  

Physical State
Solid   
Solid   

Color
Silvery White   
Silver   

Luster
Metallic   
Metallic   

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   
Np   

Isotopes
  
  

Known Isotopes
34   
5
20   
19

Electronegativity
  
  

Pauling Electronegativity
1.23   
37
1.36   
29

Allred Rochow Electronegativity
1.10   
30
1.22   
26

Electropositivity
  
  

Pauling Electropositivity
2.77   
17
2.64   
25

Ionization Energies
  
  

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

2nd Energy Level
1,140.00 kJ/mol   
99+
1,128.00 kJ/mol   
99+

3rd Energy Level
2,204.00 kJ/mol   
99+
1,997.00 kJ/mol   
99+

4th Energy Level
4,100.00 kJ/mol   
34
3,242.00 kJ/mol   
99+

Electrochemical Equivalent
2.02 g/amp-hr   
29
1.77 g/amp-hr   
39

Electron Work Function
Not Available   
Not Available   

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

Atomic Properties

Atomic Number
67   
99+
93   
25

Electron Configuration
[Xe] 4f11 6s2   
[Rn] 5f4 6d1 7s2   

Crystal Structure
Hexagonal Close Packed (HCP)   
Orthorhombic (ORTH)   

Crystal Lattice
HCP-Crystal-Structure-of-Holmium.jpg#100   
ORTH-Crystal-Structure-of-Neptunium.jpg#100   

Atom
  
  

Number of Protons
67   
99+
93   
25

Number of Neutrons
98   
34
144   
14

Number of Electrons
67   
99+
93   
25

Radius of an Atom
  
  

Atomic Radius
176.00 pm   
18
155.00 pm   
30

Covalent Radius
192.00 pm   
17
190.00 pm   
18

Van der Waals Radius
216.00 pm   
24
221.00 pm   
22

Atomic Weight
164.93 amu   
99+
237.00 amu   
22

Atomic Volume
18.70 cm3/mol   
24
11.62 cm3/mol   
99+

Adjacent Atomic Numbers
  
  

Previous Element
Dysprosium
  
Uranium
  

Next Element
Erbium
  
Plutonium
  

Valence Electron Potential
47.90 (-eV)   
31
96.00 (-eV)   
9

Lattice Constant
357.73 pm   
38
666.30 pm   
3

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

Lattice C/A Ratio
1.57   
17
Not Available   

Mechanical Properties

Density
  
  

Density At Room Temperature
8.79 g/cm3   
99+
19.38 g/cm3   
14

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

Tensile Strength
Not Available   
125.00 MPa   
14

Viscosity
Not Available   
Not Available   

Vapor Pressure
  
  

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

Vapor Pressure at 2000 K
Not Available   
0.11 (Pa)   
17

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   
Ductile   

Magnetic Properties

Magnetic Characteristics
  
  

Specific Gravity
8.80   
35
20.25   
6

Magnetic Ordering
Paramagnetic   
Paramagnetic   

Electrical Properties
  
  

Electrical Property
Conductor   
Conductor   

Resistivity
814.00 nΩ·m   
4
1.22 nΩ·m   
99+

Electrical Conductivity
0.01 106/cm Ω   
99+
0.01 106/cm Ω   
99+

Electron Affinity
50.00 kJ/mol   
21
Not Available   

Thermal Properties

Specific Heat
0.16 J/(kg K)   
35
0.12 J/(kg K)   
40

Molar Heat Capacity
27.15 J/mol·K   
19
29.46 J/mol·K   
8

Thermal Conductivity
16.20 W/m·K   
99+
6.30 W/m·K   
99+

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
3.20 kJ/mol   
99+

Enthalpy of Atomization
301.00 kJ/mol   
36
Not Available   

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

Summary >>
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