Home
Compare Metals


Osmium vs Neptunium


Neptunium vs Osmium


Periodic Table

Symbol
Os  
Np  

Group Number
8  
10
Not Available  

Period Number
6  
7  

Block
d block  
f block  

Element Family
Transition Metal  
Actinide  

CAS Number
7440042  
99+
7439998  
99+

Space Group Name
P63/mmc  
Pnma  

Space Group Number
194.00  
5
62.00  
11

Facts

Interesting Facts
  • Osmium metal does not oxidize in air unless it is heated.
  • But if it heated den it forms Osmium Tetroxide, which is highly toxic.
  
Not Available  

Sources
Found As a By-product, Found in Minerals, Mining  
Made by Bombarding Uranium with Neutrons, Ores of metals  

History
  
  

Who Discovered
Smithson Tennant  
Edwin McMillan and Philip H. Abelson  

Discovery
In 1803  
In 1940  

Abundance
  
  

Abundance In Universe
3 * 10-7 %  
21
Not Available  

Abundance In Sun
~0.0000002 %  
25
~-9999 %  

Abundance In Meteorites
0.00 %  
28
Not Available  

Abundance In Earth's Crust
0.00 %  
99+
Not Available  

Uses

Uses & Benefits
  • Its has very limited uses and its alloys are very hard and are used in the manufacturing of pen tips, pivots, needles and electrical contacts.
  • It is also used as industrial catalyst to speed up the chemical reaction.
  
  • 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
Aerospace Industry, Automobile Industry, Electrical Industry, Electronic Industry  
NA  

Medical Uses
NA  
NA  

Other Uses
Alloys  
Alloys, Nuclear Research, Research Purposes  

Biological Properties
  
  

Toxicity
Highly 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
3,045.00 °C  
3
640.00 °C  
99+

Boiling Point
5,027.00 °C  
6
3,902.00 °C  
13

Appearance
  
  

Physical State
Solid  
Solid  

Color
Silvery Bluish-Gray  
Silver  

Luster
Metallic  
Metallic  

Hardness
  
  

Mohs Hardness
7.00  
3
Not Available  

Brinell Hardness
3,490.00 MPa  
1
Not Available  

Speed of Sound
4,940.00 m/s  
11
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
Os  
Np  

Isotopes
  
  

Known Isotopes
35  
4
20  
19

Electronegativity
  
  

Pauling Electronegativity
2.20  
4
1.36  
29

Allred Rochow Electronegativity
1.52  
12
1.22  
26

Allen Electronegativity
1.65  
19
Not Available  

Electropositivity
  
  

Pauling Electropositivity
1.80  
99+
2.64  
25

Ionization Energies
  
  

1st Energy Level
840.00 kJ/mol  
12
604.50 kJ/mol  
99+

2nd Energy Level
1,309.80 kJ/mol  
99+
1,128.00 kJ/mol  
99+

3rd Energy Level
1,600.00 kJ/mol  
99+
1,997.00 kJ/mol  
99+

4th Energy Level
Not Available  
3,242.00 kJ/mol  
99+

Electrochemical Equivalent
1.77 g/amp-hr  
38
1.77 g/amp-hr  
39

Electron Work Function
4.83 eV  
8
Not Available  

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

Atomic Properties

Atomic Number
76  
40
93  
25

Electron Configuration
[Xe] 4f14 5d6 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
76  
39
93  
25

Number of Neutrons
114  
25
144  
14

Number of Electrons
76  
39
93  
25

Radius of an Atom
  
  

Atomic Radius
133.80 pm  
99+
155.00 pm  
30

Covalent Radius
Not Available  
190.00 pm  
18

Van der Waals Radius
216.00 pm  
24
221.00 pm  
22

Atomic Weight
190.23 amu  
35
237.00 amu  
22

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

Adjacent Atomic Numbers
  
  

Previous Element
Rhenium
  
Uranium
  

Next Element
Iridium
  
Plutonium
  

Valence Electron Potential
91.40 (-eV)  
12
96.00 (-eV)  
9

Lattice Constant
273.44 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  
14
Not Available  

Mechanical Properties

Density
  
  

Density At Room Temperature
22.59 g/cm3  
9
19.38 g/cm3  
14

Density When Liquid (at m.p.)
20.00 g/cm3  
1
Not Available  

Tensile Strength
1,000.00 MPa  
4
125.00 MPa  
14

Viscosity
Not Available  
Not Available  

Vapor Pressure
  
  

Vapor Pressure at 2000 K
0.00 (Pa)  
28
0.11 (Pa)  
17

Elasticity properties
  
  

Shear Modulus
222.00 GPa  
1
Not Available  

Bulk Modulus
462.00 GPa  
1
Not Available  

Poisson Ratio
0.25  
24
Not Available  

Other Mechanical Properties
Ductile  
Ductile  

Magnetic Properties

Magnetic Characteristics
  
  

Specific Gravity
22.57  
2
20.25  
6

Magnetic Ordering
Paramagnetic  
Paramagnetic  

Electrical Properties
  
  

Electrical Property
Conductor  
Conductor  

Resistivity
81.20 nΩ·m  
35
1.22 nΩ·m  
99+

Electrical Conductivity
0.11 106/cm Ω  
18
0.01 106/cm Ω  
99+

Electron Affinity
106.10 kJ/mol  
9
Not Available  

Thermal Properties

Specific Heat
0.13 J/(kg K)  
39
0.12 J/(kg K)  
40

Molar Heat Capacity
24.70 J/mol·K  
99+
29.46 J/mol·K  
8

Thermal Conductivity
87.60 W/m·K  
19
6.30 W/m·K  
99+

Critical Temperature
Not Available  
Not Available  

Thermal Expansion
5.10 µm/(m·K)  
99+
Not Available  

Enthalpy
  
  

Enthalpy of Vaporization
627.60 kJ/mol  
7
Not Available  

Enthalpy of Fusion
29.30 kJ/mol  
4
3.20 kJ/mol  
99+

Enthalpy of Atomization
669.00 kJ/mol  
6
Not Available  

Standard Molar Entropy
32.60 J/mol.K  
99+
Not Available  

Periodic Table >>
<< All

Compare Transition Metals

Transition Metals

Transition Metals

» More Transition Metals

Compare Transition Metals

» More Compare Transition Metals