Periodic Table
Symbol
Np
Group Number
3
Rank: 15 (Overall)
0
17
👆🏻
Period Number
7
Rank: 1 (Overall)
2
7
👆🏻
Block
f block
Element Family
Actinide
CAS Number
7439998
Rank: 79 (Overall)
7429905
54386242
👆🏻
Space Group Name
Pnma
Space Group Number
62.00
Rank: 14 (Overall)
11
276
👆🏻
Facts
Interesting Facts
Neptunium was the first transuranium element to be discovered.
Sources
Made by Bombarding Uranium with Neutrons, Ores of metals
History
Who Discovered
Edwin McMillan and Philip H. Abelson
Discovery
In 1940
Abundance
Abundance In Universe
0.00 %
Rank: 40 (Overall)
0
0.11
👆🏻
Abundance In Sun
0.00 %
Rank: 26 (Overall)
0
0.1
👆🏻
Abundance In Meteorites
0.00 %
Rank: 54 (Overall)
0
22
👆🏻
Abundance In Earth's Crust
0.00 %
Rank: 60 (Overall)
1E-37
8.1
👆🏻
Abundance In Oceans
-
0
1.1
👆🏻
Abundance In Humans
0.00 %
Rank: 24 (Overall)
0
1.4
👆🏻
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.
Industrial Uses
-
Medical Uses
-
Other Uses
Alloys, Nuclear Research, Research Purposes
Biological Properties
Toxicity
Toxic
Present in Human Body
✔
✘
7% - Actinide Series Metals
In Blood
0.00 Blood/mg dm-3
Rank: 40 (Overall)
0
1970
👆🏻
In Bone
0.00 p.p.m.
Rank: 41 (Overall)
0
170000
👆🏻
Physical
Melting Point
640.00 °C
Rank: 62 (Overall)
-38.83
3410
👆🏻
Boiling Point
3,902.00 °C
Rank: 13 (Overall)
0
5660
👆🏻
Appearance
Physical State
Solid
Color
Silver
Luster
Metallic
Hardness
Mohs Hardness
6.00
Rank: 6 (Overall)
0.2
8.5
👆🏻
Brinell Hardness
622.00 MPa
Rank: 23 (Overall)
0.14
3490
👆🏻
Vickers Hardness
640.00 MPa
Rank: 23 (Overall)
0
3920
👆🏻
Speed of Sound
2,260.00 m/s
Rank: 58 (Overall)
818
16200
👆🏻
Optical Properties
Refractive Index
1.30
Rank: 43 (Overall)
0.155
3.41
👆🏻
Reflectivity
64.00 %
Rank: 19 (Overall)
5
97
👆🏻
Allotropes
✔
✘
No - Actinide Series Metals has it !
α Allotropes
-
β Allotropes
-
γ Allotropes
-
Chemical
Chemical Formula
Np
Isotopes
Known Isotopes
20
Rank: 19 (Overall)
0
38
👆🏻
Electronegativity
Pauling Electronegativity
1.36
Rank: 30 (Overall)
0
2.6
👆🏻
Sanderson Electronegativity
1.36
Rank: 23 (Overall)
0.22
2.56
👆🏻
Allred Rochow Electronegativity
1.22
Rank: 27 (Overall)
0.86
1.9
👆🏻
Mulliken-Jaffe Electronegativity
1.36
Rank: 31 (Overall)
0.62
2.48
👆🏻
Allen Electronegativity
1.36
Rank: 37 (Overall)
0.659
2.7
👆🏻
Electropositivity
Pauling Electropositivity
2.64
Rank: 25 (Overall)
1.46
3.3
👆🏻
Ionization Energies
1st Energy Level
604.50 kJ/mol
Rank: 50 (Overall)
375.7
26130
👆🏻
2nd Energy Level
1,128.00 kJ/mol
Rank: 73 (Overall)
392.8
28750
👆🏻
3rd Energy Level
1,997.00 kJ/mol
Rank: 78 (Overall)
392.8
34230
👆🏻
4th Energy Level
3,242.00 kJ/mol
Rank: 72 (Overall)
375.7
37066
👆🏻
5th Energy Level
6,180.00 kJ/mol
Rank: 41 (Overall)
392
97510
👆🏻
6th Energy Level
5,785.00 kJ/mol
Rank: 69 (Overall)
1007
105800
👆🏻
7th Energy level
6,040.00 kJ/mol
Rank: 51 (Overall)
1007
114300
👆🏻
8th Energy Level
6,040.00 kJ/mol
Rank: 48 (Overall)
730
125300
👆🏻
9th Energy Level
6,180.00 kJ/mol
Rank: 44 (Overall)
1007
134700
👆🏻
10th Energy Level
6,180.00 kJ/mol
Rank: 45 (Overall)
392
144300
👆🏻
11th Energy Level
6,180.00 kJ/mol
Rank: 50 (Overall)
392
169988
👆🏻
12th Energy Level
61,800.00 kJ/mol
Rank: 13 (Overall)
0
189368
👆🏻
13th Energy Level
6,180.00 kJ/mol
Rank: 40 (Overall)
1007
76015
👆🏻
14th Energy Level
6,180.00 kJ/mol
Rank: 29 (Overall)
380
86450
👆🏻
15th Energy Level
60,600.00 kJ/mol
Rank: 42 (Overall)
33000
100700
👆🏻
16th Energy Level
60,420.00 kJ/mol
Rank: 31 (Overall)
375.7
109480
👆🏻
17th Energy Level
604.00 kJ/mol
Rank: 52 (Overall)
375.7
122200
👆🏻
18th Energy Level
6,040.00 kJ/mol
Rank: 45 (Overall)
0
134810
👆🏻
19th Energy Level
604.50 kJ/mol
Rank: 49 (Overall)
375.7
148700
👆🏻
20th Energy Level
604.00 kJ/mol
Rank: 47 (Overall)
0
171200
👆🏻
21st Energy Level
6,040.00 kJ/mol
Rank: 17 (Overall)
375.7
179100
👆🏻
22nd Energy Level
604.00 kJ/mol
Rank: 40 (Overall)
330
184900
👆🏻
23rd Energy Level
6,040.00 kJ/mol
Rank: 18 (Overall)
357.6
198800
👆🏻
24th Energy Level
604.50 kJ/mol
Rank: 42 (Overall)
297.3
195200
👆🏻
25th Energy Level
604.00 kJ/mol
Rank: 44 (Overall)
0
121900
👆🏻
26th Energy Level
604.00 kJ/mol
Rank: 43 (Overall)
357.6
127700
👆🏻
27th Energy Level
604.00 kJ/mol
Rank: 46 (Overall)
0
133800
👆🏻
28th Energy Level
604.00 kJ/mol
Rank: 50 (Overall)
297.3
139800
👆🏻
29th Energy Level
604.00 kJ/mol
Rank: 51 (Overall)
0
148100
👆🏻
30th Energy Level
604.00 kJ/mol
Rank: 47 (Overall)
0
154500
👆🏻
Electrochemical Equivalent
1.77 g/amp-hr
Rank: 43 (Overall)
0.16812
8.3209
👆🏻
Electron Work Function
4.90 eV
Rank: 12 (Overall)
2.14
6
👆🏻
Other Chemical Properties
Ionization, Radioactive Isotopes, Radioactivity, Solubility
Atomic
Atomic Number
93
Rank: 25 (Overall)
3
117
👆🏻
Electron Configuration
[Rn] 5f4 6d1 7s2
Crystal Structure
Orthorhombic (ORTH)
Crystal Lattice
Atom
Number of Protons
93
Rank: 25 (Overall)
3
117
👆🏻
Number of Neutrons
144
Rank: 15 (Overall)
4
285
👆🏻
Number of Electrons
93
Rank: 25 (Overall)
3
117
👆🏻
Radius of an Atom
Atomic Radius
155.00 pm
Rank: 32 (Overall)
0
348
👆🏻
Covalent Radius
190.00 pm
Rank: 18 (Overall)
0
260
👆🏻
Van der Waals Radius
221.00 pm
Rank: 27 (Overall)
0
348
👆🏻
Atomic Weight
237.00 amu
Rank: 22 (Overall)
6.94
294
👆🏻
Atomic Volume
11.62 cm3/mol
Rank: 61 (Overall)
1.39
71.07
👆🏻
Adjacent Atomic Numbers
Previous Element
Next Element
Valence Electron Potential
96.00 (-eV)
Rank: 9 (Overall)
0
392.42
👆🏻
Lattice Constant
666.30 pm
Rank: 3 (Overall)
0
891.25
👆🏻
Lattice Angles
π/2, π/2, π/2
Lattice C/A Ratio
1.43
Rank: 50 (Overall)
0.423
1.9
👆🏻
Mechanical
Density
Density At Room Temperature
19.38 g/cm3
Rank: 14 (Overall)
0.534
40.7
👆🏻
Density When Liquid (at m.p.)
20.25 g/cm3
Rank: 10 (Overall)
0.512
41
👆🏻
Tensile Strength
125.00 MPa
Rank: 26 (Overall)
0.1
11000
👆🏻
Viscosity
0.00
Rank: 25 (Overall)
1.5E-05
0.0035
👆🏻
Vapor Pressure
Vapor Pressure at 1000 K
0.00 (Pa)
Rank: 22 (Overall)
0
121
👆🏻
Vapor Pressure at 2000 K
0.11 (Pa)
Rank: 17 (Overall)
0
774
👆🏻
Elasticity properties
Shear Modulus
5.60 GPa
Rank: 59 (Overall)
1.3
222
👆🏻
Bulk Modulus
180.00 GPa
Rank: 9 (Overall)
0
462
👆🏻
Young's Modulus
46.00 GPa
Rank: 42 (Overall)
0
528
👆🏻
Poisson Ratio
0.26
Rank: 22 (Overall)
0.032
0.47
👆🏻
Other Mechanical Properties
Ductile
Magnetic
Magnetic Characteristics
Specific Gravity
20.25
Rank: 15 (Overall)
0.53
4500
👆🏻
Magnetic Ordering
Paramagnetic
Permeability
0.00 H/m
Rank: 6 (Overall)
1.25643E-06
0.0063
👆🏻
Susceptibility
0.00
Rank: 24 (Overall)
-0.000166
200000
👆🏻
Electrical Properties
Electrical Property
Conductor
Resistivity
1.22 nΩ·m
Rank: 71 (Overall)
0.1
961
👆🏻
Electrical Conductivity
0.01 106/cm Ω
Rank: 66 (Overall)
0
0.63
👆🏻
Electron Affinity
118.60 kJ/mol
Rank: 6 (Overall)
0
222.8
👆🏻
Thermal
Specific Heat
0.12 J/(kg K)
Rank: 42 (Overall)
0.1
3.6
👆🏻
Molar Heat Capacity
29.46 J/mol·K
Rank: 10 (Overall)
13.1
62.7
👆🏻
Thermal Conductivity
6.30 W/m·K
Rank: 73 (Overall)
0
429
👆🏻
Critical Temperature
913.00 K
Rank: 64 (Overall)
26.3
3695
👆🏻
Thermal Expansion
13.30 µm/(m·K)
Rank: 35 (Overall)
4.5
97
👆🏻
Enthalpy
Enthalpy of Vaporization
336.00 kJ/mol
Rank: 39 (Overall)
7.32
799.1
👆🏻
Enthalpy of Fusion
3.20 kJ/mol
Rank: 63 (Overall)
2.1
35.23
👆🏻
Enthalpy of Atomization
275.30 kJ/mol
Rank: 51 (Overall)
61.5
837
👆🏻
Standard Molar Entropy
64.00 J/mol.K
Rank: 21 (Overall)
9.5
198.1
👆🏻