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Hafnium vs Neptunium


Neptunium vs Hafnium


Periodic Table

Symbol
Hf  
Np  

Group Number
4  
14
3  
15

Period Number
6  
7  

Block
d block  
f block  

Element Family
Transition Metal  
Actinide  

CAS Number
7440586  
30
7439998  
99+

Space Group Name
P63/mmc  
Pnma  

Space Group Number
194.00  
7
62.00  
14

Facts

Interesting Facts
  • Hafnium metal is highly reactive, hence not found free in nature.
  • Hafnium metal as predicated after Mendeleev finished his periodic table.
  
Neptunium was the first transuranium element to be discovered.  

Sources
By-product Zirconium Refining  
Made by Bombarding Uranium with Neutrons, Ores of metals  

History
  
  

Who Discovered
Dirk Coster and George de Hevesy  
Edwin McMillan and Philip H. Abelson  

Discovery
In 1922  
In 1940  

Abundance
  
  

Abundance In Universe
0.00 %  
26
0.00 %  
40

Abundance In Sun
0.00 %  
26
0.00 %  
26

Abundance In Meteorites
0.00 %  
37
0.00 %  
99+

Abundance In Earth's Crust
0.00 %  
31
0.00 %  
99+

Abundance In Oceans
0.00 %  
27
-  

Abundance In Humans
0.00 %  
14
0.00 %  
24

Uses

Uses & Benefits
  • It has an ability to absorb neutrons and hence it is used to make control rods in nuclear submarines. And this metal is also used in Plasma welding torches.
  • It alloys with iron, titanium and niobium are very useful.
  
  • 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
Ammunition Industry  
-  

Medical Uses
-  
-  

Other Uses
Alloys, In Nuclear Reactors, Nuclear Research, Research Purposes  
Alloys, Nuclear Research, Research Purposes  

Biological Properties
  
  

Toxicity
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
2,150.00 °C  
10
640.00 °C  
99+

Boiling Point
5,400.00 °C  
5
3,902.00 °C  
13

Appearance
  
  

Physical State
Solid  
Solid  

Color
Gray  
Silver  

Luster
Metallic  
Metallic  

Hardness
  
  

Mohs Hardness
5.50  
7
6.00  
6

Brinell Hardness
1,450.00 MPa  
6
622.00 MPa  
23

Vickers Hardness
1,520.00 MPa  
10
640.00 MPa  
23

Speed of Sound
3,010.00 m/s  
39
2,260.00 m/s  
99+

Optical Properties
  
  

Refractive Index
2.00  
15
1.30  
99+

Reflectivity
71.00 %  
12
64.00 %  
19

Allotropes
No  
No  

α Allotropes
-  
-  

β Allotropes
-  
-  

γ Allotropes
-  
-  

Chemical

Chemical Formula
Hf  
Np  

Isotopes
  
  

Known Isotopes
32  
7
20  
19

Electronegativity
  
  

Pauling Electronegativity
1.30  
33
1.36  
30

Sanderson Electronegativity
1.30  
25
1.36  
23

Allred Rochow Electronegativity
1.23  
26
1.22  
27

Mulliken-Jaffe Electronegativity
1.30  
33
1.36  
31

Allen Electronegativity
1.16  
99+
1.36  
37

Electropositivity
  
  

Pauling Electropositivity
2.70  
22
2.64  
25

Ionization Energies
  
  

1st Energy Level
658.50 kJ/mol  
40
604.50 kJ/mol  
99+

2nd Energy Level
1,440.00 kJ/mol  
99+
1,128.00 kJ/mol  
99+

3rd Energy Level
2,250.00 kJ/mol  
99+
1,997.00 kJ/mol  
99+

4th Energy Level
3,216.00 kJ/mol  
99+
3,242.00 kJ/mol  
99+

5th Energy Level
6,585.00 kJ/mol  
33
6,180.00 kJ/mol  
99+

6th Energy Level
6,585.00 kJ/mol  
99+
5,785.00 kJ/mol  
99+

7th Energy level
6,580.00 kJ/mol  
99+
6,040.00 kJ/mol  
99+

8th Energy Level
6,580.00 kJ/mol  
99+
6,040.00 kJ/mol  
99+

9th Energy Level
6,585.00 kJ/mol  
38
6,180.00 kJ/mol  
99+

10th Energy Level
6,590.00 kJ/mol  
40
6,180.00 kJ/mol  
99+

11th Energy Level
6,585.00 kJ/mol  
40
6,180.00 kJ/mol  
99+

12th Energy Level
6,580.00 kJ/mol  
99+
61,800.00 kJ/mol  
13

13th Energy Level
6,580.00 kJ/mol  
35
6,180.00 kJ/mol  
40

14th Energy Level
658.50 kJ/mol  
99+
6,180.00 kJ/mol  
29

15th Energy Level
65,800.00 kJ/mol  
34
60,600.00 kJ/mol  
99+

16th Energy Level
658.50 kJ/mol  
99+
60,420.00 kJ/mol  
31

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

18th Energy Level
6,585.00 kJ/mol  
36
6,040.00 kJ/mol  
99+

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

20th Energy Level
658.00 kJ/mol  
37
604.00 kJ/mol  
99+

21st Energy Level
658.50 kJ/mol  
99+
6,040.00 kJ/mol  
17

22nd Energy Level
658.00 kJ/mol  
31
604.00 kJ/mol  
40

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

24th Energy Level
658.50 kJ/mol  
31
604.50 kJ/mol  
99+

25th Energy Level
658.00 kJ/mol  
33
604.00 kJ/mol  
99+

26th Energy Level
658.50 kJ/mol  
32
604.00 kJ/mol  
99+

27th Energy Level
658.50 kJ/mol  
33
604.00 kJ/mol  
99+

28th Energy Level
658.50 kJ/mol  
38
604.00 kJ/mol  
99+

29th Energy Level
658.50 kJ/mol  
39
604.00 kJ/mol  
99+

30th Energy Level
658.00 kJ/mol  
35
604.00 kJ/mol  
99+

Electrochemical Equivalent
1.66 g/amp-hr  
99+
1.77 g/amp-hr  
99+

Electron Work Function
3.90 eV  
36
4.90 eV  
12

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

Atomic

Atomic Number
72  
99+
93  
25

Electron Configuration
[Xe] 4f14 5d2 6s2  
[Rn] 5f4 6d1 7s2  

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

Crystal Lattice
BCC-Crystal-Structure-.jpg#100  
ORTH-Crystal-Structure-of-Neptunium.jpg#100  

Atom
  
  

Number of Protons
72  
99+
93  
25

Number of Neutrons
106  
30
144  
15

Number of Electrons
72  
99+
93  
25

Radius of an Atom
  
  

Atomic Radius
159.00 pm  
30
155.00 pm  
32

Covalent Radius
175.00 pm  
25
190.00 pm  
18

Van der Waals Radius
200.00 pm  
35
221.00 pm  
27

Atomic Weight
178.49 amu  
39
237.00 amu  
22

Atomic Volume
13.60 cm3/mol  
99+
11.62 cm3/mol  
99+

Adjacent Atomic Numbers
  
  

Previous Element
Lutetium
  
Uranium
  

Next Element
Tantalum
  
Plutonium
  

Valence Electron Potential
81.00 (-eV)  
16
96.00 (-eV)  
9

Lattice Constant
319.64 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
1.58  
34
1.43  
99+

Mechanical

Density
  
  

Density At Room Temperature
13.31 g/cm3  
27
19.38 g/cm3  
14

Density When Liquid (at m.p.)
12.00 g/cm3  
31
20.25 g/cm3  
10

Tensile Strength
445.00 MPa  
9
125.00 MPa  
26

Viscosity
0.00  
28
0.00  
25

Vapor Pressure
  
  

Vapor Pressure at 1000 K
0.00 (Pa)  
37
0.00 (Pa)  
22

Vapor Pressure at 2000 K
0.00 (Pa)  
25
0.11 (Pa)  
17

Elasticity properties
  
  

Shear Modulus
30.00 GPa  
27
5.60 GPa  
99+

Bulk Modulus
110.00 GPa  
15
180.00 GPa  
9

Young's Modulus
78.00 GPa  
27
46.00 GPa  
99+

Poisson Ratio
0.37  
7
0.26  
22

Other Mechanical Properties
Ductile, Malleable  
Ductile  

Magnetic

Magnetic Characteristics
  
  

Specific Gravity
13.31  
30
20.25  
15

Magnetic Ordering
Paramagnetic  
Paramagnetic  

Permeability
0.00 H/m  
9
0.00 H/m  
6

Susceptibility
0.00  
13
0.00  
24

Electrical Properties
  
  

Electrical Property
Conductor  
Conductor  

Resistivity
331.00 nΩ·m  
14
1.22 nΩ·m  
99+

Electrical Conductivity
0.03 106/cm Ω  
99+
0.01 106/cm Ω  
99+

Electron Affinity
0.00 kJ/mol  
99+
118.60 kJ/mol  
6

Thermal

Specific Heat
0.14 J/(kg K)  
38
0.12 J/(kg K)  
99+

Molar Heat Capacity
25.73 J/mol·K  
99+
29.46 J/mol·K  
10

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

Critical Temperature
2,500.00 K  
11
913.00 K  
99+

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

Enthalpy
  
  

Enthalpy of Vaporization
661.10 kJ/mol  
6
336.00 kJ/mol  
39

Enthalpy of Fusion
25.10 kJ/mol  
8
3.20 kJ/mol  
99+

Enthalpy of Atomization
703.00 kJ/mol  
5
275.30 kJ/mol  
99+

Standard Molar Entropy
43.60 J/mol.K  
99+
64.00 J/mol.K  
21

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