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Erbium vs Neptunium


Neptunium vs Erbium


Periodic Table

Symbol
Er  
Np  

Group Number
3  
15
3  
15

Period Number
6  
7  

Block
f block  
f block  

Element Family
Lanthanide  
Actinide  

CAS Number
7440520  
35
7439998  
99+

Space Group Name
P63/mmc  
Pnma  

Space Group Number
194.00  
7
62.00  
14

Facts

Interesting Facts
  • Erbium metal is used as alloyed with Vanadium to make it softer.
  • Recent studies shows that it is helpful for metabolism.
  
Neptunium was the first transuranium element to be discovered.  

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

History
  
  

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

Discovery
In 1842  
In 1940  

Abundance
  
  

Abundance In Universe
0.00 %  
23
0.00 %  
40

Abundance In Sun
0.00 %  
26
0.00 %  
26

Abundance In Meteorites
0.00 %  
36
0.00 %  
99+

Abundance In Earth's Crust
0.00 %  
32
0.00 %  
99+

Abundance In Oceans
0.00 %  
36
-  

Abundance In Humans
0.00 %  
24
0.00 %  
24

Uses

Uses & Benefits
  • 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.
  
  • 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
Chemical Industry  
-  

Medical Uses
-  
-  

Other Uses
Alloys  
Alloys, Nuclear Research, Research Purposes  

Biological Properties
  
  

Toxicity
Mildly Toxic  
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
1,522.00 °C  
28
640.00 °C  
99+

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

Appearance
  
  

Physical State
Solid  
Solid  

Color
Silvery White  
Silver  

Luster
Lustrous  
Metallic  

Hardness
  
  

Mohs Hardness
1.00  
22
6.00  
6

Brinell Hardness
814.00 MPa  
12
622.00 MPa  
23

Vickers Hardness
589.00 MPa  
30
640.00 MPa  
23

Speed of Sound
2,830.00 m/s  
99+
2,260.00 m/s  
99+

Optical Properties
  
  

Refractive Index
1.76  
24
1.30  
99+

Reflectivity
36.00 %  
33
64.00 %  
19

Allotropes
No  
No  

α Allotropes
-  
-  

β Allotropes
-  
-  

γ Allotropes
-  
-  

Chemical

Chemical Formula
Er  
Np  

Isotopes
  
  

Known Isotopes
31  
8
20  
19

Electronegativity
  
  

Pauling Electronegativity
1.24  
37
1.36  
30

Sanderson Electronegativity
1.24  
29
1.36  
23

Allred Rochow Electronegativity
1.11  
30
1.22  
27

Mulliken-Jaffe Electronegativity
1.24  
36
1.36  
31

Allen Electronegativity
1.24  
99+
1.36  
37

Electropositivity
  
  

Pauling Electropositivity
2.76  
18
2.64  
25

Ionization Energies
  
  

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

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

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

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

5th Energy Level
5,897.00 kJ/mol  
99+
6,180.00 kJ/mol  
99+

6th Energy Level
5,897.00 kJ/mol  
99+
5,785.00 kJ/mol  
99+

7th Energy level
5,890.00 kJ/mol  
99+
6,040.00 kJ/mol  
99+

8th Energy Level
5,890.00 kJ/mol  
99+
6,040.00 kJ/mol  
99+

9th Energy Level
4,240.00 kJ/mol  
99+
6,180.00 kJ/mol  
99+

10th Energy Level
5,890.00 kJ/mol  
99+
6,180.00 kJ/mol  
99+

11th Energy Level
5,890.00 kJ/mol  
99+
6,180.00 kJ/mol  
99+

12th Energy Level
5,890.00 kJ/mol  
99+
61,800.00 kJ/mol  
13

13th Energy Level
5,890.00 kJ/mol  
99+
6,180.00 kJ/mol  
40

14th Energy Level
5,890.00 kJ/mol  
37
6,180.00 kJ/mol  
29

15th Energy Level
58,900.00 kJ/mol  
99+
60,600.00 kJ/mol  
99+

16th Energy Level
58,900.00 kJ/mol  
38
60,420.00 kJ/mol  
31

17th Energy Level
589.30 kJ/mol  
99+
604.00 kJ/mol  
99+

18th Energy Level
5,890.00 kJ/mol  
99+
6,040.00 kJ/mol  
99+

19th Energy Level
589.30 kJ/mol  
99+
604.50 kJ/mol  
99+

20th Energy Level
589.00 kJ/mol  
99+
604.00 kJ/mol  
99+

21st Energy Level
5,897.00 kJ/mol  
19
6,040.00 kJ/mol  
17

22nd Energy Level
589.00 kJ/mol  
99+
604.00 kJ/mol  
40

23rd Energy Level
589.30 kJ/mol  
99+
6,040.00 kJ/mol  
18

24th Energy Level
589.30 kJ/mol  
99+
604.50 kJ/mol  
99+

25th Energy Level
589.00 kJ/mol  
99+
604.00 kJ/mol  
99+

26th Energy Level
589.30 kJ/mol  
99+
604.00 kJ/mol  
99+

27th Energy Level
589.30 kJ/mol  
99+
604.00 kJ/mol  
99+

28th Energy Level
589.30 kJ/mol  
99+
604.00 kJ/mol  
99+

29th Energy Level
589.30 kJ/mol  
99+
604.00 kJ/mol  
99+

30th Energy Level
589.70 kJ/mol  
99+
604.00 kJ/mol  
99+

Electrochemical Equivalent
2.08 g/amp-hr  
32
1.77 g/amp-hr  
99+

Electron Work Function
5.93 eV  
2
4.90 eV  
12

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

Atomic

Atomic Number
68  
99+
93  
25

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

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

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

Atom
  
  

Number of Protons
68  
99+
93  
25

Number of Neutrons
99  
34
144  
15

Number of Electrons
68  
99+
93  
25

Radius of an Atom
  
  

Atomic Radius
176.00 pm  
20
155.00 pm  
32

Covalent Radius
189.00 pm  
19
190.00 pm  
18

Van der Waals Radius
0.00 pm  
99+
221.00 pm  
27

Atomic Weight
167.26 amu  
99+
237.00 amu  
22

Atomic Volume
18.40 cm3/mol  
37
11.62 cm3/mol  
99+

Adjacent Atomic Numbers
  
  

Previous Element
Holmium
  
Uranium
  

Next Element
Thulium
  
Plutonium
  

Valence Electron Potential
49.00 (-eV)  
30
96.00 (-eV)  
9

Lattice Constant
355.88 pm  
99+
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  
40
1.43  
99+

Mechanical

Density
  
  

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

Density When Liquid (at m.p.)
8.86 g/cm3  
99+
20.25 g/cm3  
10

Tensile Strength
350.00 MPa  
12
125.00 MPa  
26

Viscosity
0.00  
25
0.00  
25

Vapor Pressure
  
  

Vapor Pressure at 1000 K
0.00 (Pa)  
21
0.00 (Pa)  
22

Vapor Pressure at 2000 K
0.00 (Pa)  
30
0.11 (Pa)  
17

Elasticity properties
  
  

Shear Modulus
28.30 GPa  
31
5.60 GPa  
99+

Bulk Modulus
44.40 GPa  
31
180.00 GPa  
9

Young's Modulus
69.90 GPa  
31
46.00 GPa  
99+

Poisson Ratio
0.24  
28
0.26  
22

Other Mechanical Properties
Malleable  
Ductile  

Magnetic

Magnetic Characteristics
  
  

Specific Gravity
9.07  
99+
20.25  
15

Magnetic Ordering
Paramagnetic  
Paramagnetic  

Permeability
0.00 H/m  
17
0.00 H/m  
6

Susceptibility
0.00  
11
0.00  
24

Electrical Properties
  
  

Electrical Property
Conductor  
Conductor  

Resistivity
0.86 nΩ·m  
99+
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  
26
118.60 kJ/mol  
6

Thermal

Specific Heat
0.17 J/(kg K)  
35
0.12 J/(kg K)  
99+

Molar Heat Capacity
28.12 J/mol·K  
14
29.46 J/mol·K  
10

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

Critical Temperature
1,802.00 K  
30
913.00 K  
99+

Thermal Expansion
12.20 µm/(m·K)  
99+
13.30 µm/(m·K)  
35

Enthalpy
  
  

Enthalpy of Vaporization
261.00 kJ/mol  
99+
336.00 kJ/mol  
39

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

Enthalpy of Atomization
314.00 kJ/mol  
99+
275.30 kJ/mol  
99+

Standard Molar Entropy
73.10 J/mol.K  
11
64.00 J/mol.K  
21

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