Home
Compare Metals


Neptunium vs Erbium


Erbium vs Neptunium


Periodic Table

Symbol
Np   
Er   

Group Number
Not Available   
Not Available   

Period Number
7   
6   

Block
f block   
f block   

Element Family
Actinide   
Lanthanide   

CAS Number
7439998   
99+
7440520   
35

Space Group Name
Pnma   
P63/mmc   

Space Group Number
62.00   
11
194.00   
5

Facts

Interesting Facts
Not Available   
  • Erbium metal is used as alloyed with Vanadium to make it softer.
  • Recent studies shows that it is helpful for metabolism.
  

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

History
  
  

Who Discovered
Edwin McMillan and Philip H. Abelson   
Carl Gustaf Mosander   

Discovery
In 1940   
In 1842   

Abundance
  
  

Abundance In Universe
Not Available   
2 * 10-7 %   
22

Abundance In Sun
~-9999 %   
~0.0000001 %   
26

Abundance In Meteorites
Not Available   
0.00 %   
36

Abundance In Earth's Crust
Not Available   
0.00 %   
32

Abundance In Oceans
Not Available   
0.00 %   
36

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.
  
  • It has a tendency to get tarnished in the open air, but when alloyed with elements like erbium, vanadium, its hardness levels decreases.
  • Its compounds like Erbium oxide is used in safety glasses of welders and metal workers.
  

Industrial Uses
NA   
Chemical Industry   

Medical Uses
NA   
NA   

Other Uses
Alloys, Nuclear Research, Research Purposes   
Alloys   

Biological Properties
  
  

Toxicity
Toxic   
Mildly Toxic   

Present in Human Body
No   
No   

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

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

Physical Properties

Melting Point
640.00 °C   
99+
1,522.00 °C   
28

Boiling Point
3,902.00 °C   
13
2,510.00 °C   
99+

Appearance
  
  

Physical State
Solid   
Solid   

Color
Silver   
Silvery White   

Luster
Metallic   
Lustrous   

Hardness
  
  

Brinell Hardness
Not Available   
814.00 MPa   
11

Vickers Hardness
Not Available   
589.00 MPa   
19

Speed of Sound
Not Available   
2,830.00 m/s   
28

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
Np   
Er   

Isotopes
  
  

Known Isotopes
20   
19
31   
8

Electronegativity
  
  

Pauling Electronegativity
1.36   
29
1.24   
36

Allred Rochow Electronegativity
1.22   
26
1.11   
29

Electropositivity
  
  

Pauling Electropositivity
2.64   
25
2.76   
18

Ionization Energies
  
  

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

2nd Energy Level
1,128.00 kJ/mol   
99+
1,150.00 kJ/mol   
99+

3rd Energy Level
1,997.00 kJ/mol   
99+
2,194.00 kJ/mol   
99+

4th Energy Level
3,242.00 kJ/mol   
99+
4,120.00 kJ/mol   
33

Electrochemical Equivalent
1.77 g/amp-hr   
39
2.08 g/amp-hr   
28

Electron Work Function
Not Available   
Not Available   

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

Atomic Properties

Atomic Number
93   
25
68   
99+

Electron Configuration
[Rn] 5f4 6d1 7s2   
[Xe] 4f12 6s2   

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

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

Atom
  
  

Number of Protons
93   
25
68   
99+

Number of Neutrons
144   
14
99   
33

Number of Electrons
93   
25
68   
99+

Radius of an Atom
  
  

Atomic Radius
155.00 pm   
30
176.00 pm   
18

Covalent Radius
190.00 pm   
18
189.00 pm   
19

Van der Waals Radius
221.00 pm   
22
Not Available   

Atomic Weight
237.00 amu   
22
167.26 amu   
99+

Atomic Volume
11.62 cm3/mol   
99+
18.40 cm3/mol   
25

Adjacent Atomic Numbers
  
  

Previous Element
Uranium
  
Holmium
  

Next Element
Plutonium
  
Thulium
  

Valence Electron Potential
96.00 (-eV)   
9
49.00 (-eV)   
29

Lattice Constant
666.30 pm   
3
355.88 pm   
39

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

Lattice C/A Ratio
Not Available   
1.57   
17

Mechanical Properties

Density
  
  

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

Density When Liquid (at m.p.)
Not Available   
8.86 g/cm3   
23

Tensile Strength
125.00 MPa   
14
Not Available   

Viscosity
Not Available   
Not Available   

Vapor Pressure
  
  

Vapor Pressure at 1000 K
Not Available   
0.00 (Pa)   
20

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

Elasticity properties
  
  

Shear Modulus
Not Available   
28.30 GPa   
25

Bulk Modulus
Not Available   
44.40 GPa   
27

Young's Modulus
Not Available   
69.90 GPa   
29

Poisson Ratio
Not Available   
0.24   
28

Other Mechanical Properties
Ductile   
Malleable   

Magnetic Properties

Magnetic Characteristics
  
  

Specific Gravity
20.25   
6
9.07   
32

Magnetic Ordering
Paramagnetic   
Paramagnetic   

Electrical Properties
  
  

Electrical Property
Conductor   
Conductor   

Resistivity
1.22 nΩ·m   
99+
0.86 nΩ·m   
99+

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

Electron Affinity
Not Available   
50.00 kJ/mol   
21

Thermal Properties

Specific Heat
0.12 J/(kg K)   
40
0.17 J/(kg K)   
34

Molar Heat Capacity
29.46 J/mol·K   
8
28.12 J/mol·K   
11

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

Critical Temperature
Not Available   
Not Available   

Thermal Expansion
Not Available   
12.20 µm/(m·K)   
31

Enthalpy
  
  

Enthalpy of Vaporization
Not Available   
261.00 kJ/mol   
35

Enthalpy of Fusion
3.20 kJ/mol   
99+
17.20 kJ/mol   
15

Enthalpy of Atomization
Not Available   
314.00 kJ/mol   
33

Standard Molar Entropy
Not Available   
73.10 J/mol.K   
11

Periodic Table >>
<< All

Compare Actinide Series

Actinide Metals

Actinide Metals

» More Actinide Metals

Compare Actinide Series

» More Compare Actinide Series