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Neptunium vs Holmium

Neptunium
Holmium
Holmium vs Neptunium


Periodic Table
Symbol
Np  
Ho  
Group Number
3  
15
3  
15
Period Number
7  
6  
Block
f block  
f block  
Element Family
Actinide  
Lanthanide  
CAS Number
7439998  
99+
7440600  
29
Space Group Name
Pnma  
P63/mmc  
Space Group Number
62.00  
14
194.00  
7
Facts
Interesting Facts
Neptunium was the first transuranium element to be discovered.  
  • Holmium metal is very soft and malleable.
  • Holmium metal is well known for its corrosion resistivity.
  
Sources
Made by Bombarding Uranium with Neutrons, Ores of metals  
Found in Minerals, Mining, Ores of Minerals  
History
  
  
Who Discovered
Edwin McMillan and Philip H. Abelson  
Marc Delafontaine  
Discovery
In 1940  
In 1878  
Abundance
  
  
Abundance In Universe
0.00 %  
40
0.00 %  
28
Abundance In Sun
0.00 %  
26
-  
Abundance In Meteorites
0.00 %  
99+
0.00 %  
99+
Abundance In Earth's Crust
0.00 %  
99+
0.00 %  
38
Abundance In Oceans
-  
0.00 %  
99+
Abundance In Humans
0.00 %  
24
0.00 %  
24
Uses
Uses & Benefits
  • Currently known uses of Neptunium metal are limited to research purpose only.
  • Neptunium’s isotope neptunium-237 is used as a neutron detectors.
  
  • 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.
  
Industrial Uses
-  
-  
Medical Uses
-  
-  
Other Uses
Alloys, Nuclear Research, Research Purposes  
Alloys, Nuclear Research  
Biological Properties
  
  
Toxicity
Toxic  
Low Toxic  
Present in Human Body
No  
No  
In Blood
0.00 Blood/mg dm-3  
40
0.00 Blood/mg dm-3  
40
In Bone
0.00 p.p.m.  
99+
0.00 p.p.m.  
99+
Physical
Melting Point
640.00 °C  
99+
1,461.00 °C  
30
Boiling Point
3,902.00 °C  
13
2,600.00 °C  
99+
Appearance
  
  
Physical State
Solid  
Solid  
Color
Silver  
Silvery White  
Luster
Metallic  
Metallic  
Hardness
  
  
Mohs Hardness
6.00  
6
4.00  
11
Brinell Hardness
622.00 MPa  
23
746.00 MPa  
14
Vickers Hardness
640.00 MPa  
23
481.00 MPa  
36
Speed of Sound
2,260.00 m/s  
99+
2,760.00 m/s  
99+
Optical Properties
  
  
Refractive Index
1.30  
99+
1.67  
29
Reflectivity
64.00 %  
19
67.00 %  
16
Allotropes
No  
No  
α Allotropes
-  
-  
β Allotropes
-  
-  
γ Allotropes
-  
-  
Chemical
Chemical Formula
Np  
Ho  
Isotopes
  
  
Known Isotopes
20  
19
34  
5
Electronegativity
  
  
Pauling Electronegativity
1.36  
30
1.23  
38
Sanderson Electronegativity
1.36  
23
1.23  
30
Allred Rochow Electronegativity
1.22  
27
1.10  
31
Mulliken-Jaffe Electronegativity
1.36  
31
1.23  
37
Allen Electronegativity
1.36  
37
1.23  
99+
Electropositivity
  
  
Pauling Electropositivity
2.64  
25
2.77  
17
Ionization Energies
  
  
1st Energy Level
604.50 kJ/mol  
99+
581.00 kJ/mol  
99+
2nd Energy Level
1,128.00 kJ/mol  
99+
1,140.00 kJ/mol  
99+
3rd Energy Level
1,997.00 kJ/mol  
99+
2,204.00 kJ/mol  
99+
4th Energy Level
3,242.00 kJ/mol  
99+
4,100.00 kJ/mol  
99+
5th Energy Level
6,180.00 kJ/mol  
99+
5,810.00 kJ/mol  
99+
6th Energy Level
5,785.00 kJ/mol  
99+
5,810.00 kJ/mol  
99+
7th Energy level
6,040.00 kJ/mol  
99+
5,810.00 kJ/mol  
99+
8th Energy Level
6,040.00 kJ/mol  
99+
5,810.00 kJ/mol  
99+
9th Energy Level
6,180.00 kJ/mol  
99+
6,500.00 kJ/mol  
39
10th Energy Level
6,180.00 kJ/mol  
99+
6,500.00 kJ/mol  
99+
11th Energy Level
6,180.00 kJ/mol  
99+
5,810.00 kJ/mol  
99+
12th Energy Level
61,800.00 kJ/mol  
13
5,810.00 kJ/mol  
99+
13th Energy Level
6,180.00 kJ/mol  
40
5,810.00 kJ/mol  
99+
14th Energy Level
6,180.00 kJ/mol  
29
5,810.00 kJ/mol  
40
15th Energy Level
60,600.00 kJ/mol  
99+
58,100.00 kJ/mol  
99+
16th Energy Level
60,420.00 kJ/mol  
31
581.00 kJ/mol  
99+
17th Energy Level
604.00 kJ/mol  
99+
581.00 kJ/mol  
99+
18th Energy Level
6,040.00 kJ/mol  
99+
5,810.00 kJ/mol  
99+
19th Energy Level
604.50 kJ/mol  
99+
581.00 kJ/mol  
99+
20th Energy Level
604.00 kJ/mol  
99+
581.00 kJ/mol  
99+
21st Energy Level
6,040.00 kJ/mol  
17
581.00 kJ/mol  
99+
22nd Energy Level
604.00 kJ/mol  
40
581.00 kJ/mol  
99+
23rd Energy Level
6,040.00 kJ/mol  
18
5,810.00 kJ/mol  
20
24th Energy Level
604.50 kJ/mol  
99+
581.00 kJ/mol  
99+
25th Energy Level
604.00 kJ/mol  
99+
581.00 kJ/mol  
99+
26th Energy Level
604.00 kJ/mol  
99+
581.00 kJ/mol  
99+
27th Energy Level
604.00 kJ/mol  
99+
584.70 kJ/mol  
99+
28th Energy Level
604.00 kJ/mol  
99+
581.00 kJ/mol  
99+
29th Energy Level
604.00 kJ/mol  
99+
584.70 kJ/mol  
99+
30th Energy Level
604.00 kJ/mol  
99+
581.00 kJ/mol  
99+
Electrochemical Equivalent
1.77 g/amp-hr  
99+
2.02 g/amp-hr  
33
Electron Work Function
4.90 eV  
12
4.90 eV  
12
Other Chemical Properties
Ionization, Radioactive Isotopes, Radioactivity, Solubility  
Chemical Stability, Anti Corrosion, Ionization, Radioactive Isotopes, Solubility  
Atomic
Atomic Number
93  
25
67  
99+
Electron Configuration
[Rn] 5f4 6d1 7s2  
[Xe] 4f11 6s2  
Crystal Structure
Orthorhombic (ORTH)  
Hexagonal Close Packed (HCP)  
Crystal Lattice
ORTH-Crystal-Structure-of-Neptunium.jpg#100  
HCP-Crystal-Structure-of-Holmium.jpg#100  
Atom
  
  
Number of Protons
93  
25
67  
99+
Number of Neutrons
144  
15
98  
35
Number of Electrons
93  
25
67  
99+
Radius of an Atom
  
  
Atomic Radius
155.00 pm  
32
176.00 pm  
20
Covalent Radius
190.00 pm  
18
192.00 pm  
17
Van der Waals Radius
221.00 pm  
27
216.00 pm  
30
Atomic Weight
237.00 amu  
22
164.93 amu  
99+
Atomic Volume
11.62 cm3/mol  
99+
18.70 cm3/mol  
36
Adjacent Atomic Numbers
  
  
Previous Element
Uranium
  
Dysprosium
  
Next Element
Plutonium
  
Erbium
  
Valence Electron Potential
96.00 (-eV)  
9
47.90 (-eV)  
32
Lattice Constant
666.30 pm  
3
357.73 pm  
99+
Lattice Angles
π/2, π/2, π/2  
π/2, π/2, 2 π/3  
Lattice C/A Ratio
1.43  
99+
1.57  
40
Mechanical
Density
  
  
Density At Room Temperature
19.38 g/cm3  
14
8.79 g/cm3  
99+
Density When Liquid (at m.p.)
20.25 g/cm3  
10
8.34 g/cm3  
99+
Tensile Strength
125.00 MPa  
26
270.00 MPa  
17
Viscosity
0.00  
25
0.00  
25
Vapor Pressure
  
  
Vapor Pressure at 1000 K
0.00 (Pa)  
22
0.00 (Pa)  
17
Vapor Pressure at 2000 K
0.11 (Pa)  
17
0.00 (Pa)  
30
Elasticity properties
  
  
Shear Modulus
5.60 GPa  
99+
26.30 GPa  
35
Bulk Modulus
180.00 GPa  
9
40.20 GPa  
37
Young's Modulus
46.00 GPa  
99+
64.80 GPa  
33
Poisson Ratio
0.26  
22
0.23  
29
Other Mechanical Properties
Ductile  
Ductile, Malleable, Sectile  
Magnetic
Magnetic Characteristics
  
  
Specific Gravity
20.25  
15
8.80  
99+
Magnetic Ordering
Paramagnetic  
Paramagnetic  
Permeability
0.00 H/m  
6
0.00 H/m  
7
Susceptibility
0.00  
24
0.00  
11
Electrical Properties
  
  
Electrical Property
Conductor  
Conductor  
Resistivity
1.22 nΩ·m  
99+
814.00 nΩ·m  
4
Electrical Conductivity
0.01 106/cm Ω  
99+
0.01 106/cm Ω  
99+
Electron Affinity
118.60 kJ/mol  
6
50.00 kJ/mol  
26
Thermal
Specific Heat
0.12 J/(kg K)  
99+
0.16 J/(kg K)  
36
Molar Heat Capacity
29.46 J/mol·K  
10
27.15 J/mol·K  
25
Thermal Conductivity
6.30 W/m·K  
99+
16.20 W/m·K  
99+
Critical Temperature
913.00 K  
99+
1,747.00 K  
34
Thermal Expansion
13.30 µm/(m·K)  
35
11.20 µm/(m·K)  
99+
Enthalpy
  
  
Enthalpy of Vaporization
336.00 kJ/mol  
39
241.00 kJ/mol  
99+
Enthalpy of Fusion
3.20 kJ/mol  
99+
11.76 kJ/mol  
35
Enthalpy of Atomization
275.30 kJ/mol  
99+
301.00 kJ/mol  
99+
Standard Molar Entropy
64.00 J/mol.K  
21
75.30 J/mol.K  
8
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