Properties of Neptunium and Nickel
Melting Point
1,453.00 °C
  
31
Boiling Point
3,902.00 °C
  
13
2,732.00 °C
  
38
Hardness
  
  
Mohs Hardness
Not Available
  
Brinell Hardness
Not Available
  
Vickers Hardness
Not Available
  
Optical Properties
  
  
Refractive Index
Not Available
  
Not Available
  
Reflectivity
Not Available
  
Speed of Sound
Not Available
  
4,900.00 m/s
  
12
Allotropes
No
  
No
  
α Allotropes
Not Available
  
Not Available
  
β Allotropes
Not Available
  
Not Available
  
γ Allotropes
Not Available
  
Not Available
  
Chemical Formula
Np
  
Ni
  
Isotopes
  
  
Electronegativity
  
  
Pauling Electronegativity
Sanderson Electronegativity
Not Available
  
Allred Rochow Electronegativity
Mulliken-Jaffe Electronegativity
Not Available
  
Not Available
  
Allen Electronegativity
Not Available
  
Electropositivity
  
  
Pauling Electropositivity
Ionization Energies
  
  
1st Energy Level
604.50 kJ/mol
  
99+
737.10 kJ/mol
  
25
2nd Energy Level
1,128.00 kJ/mol
  
99+
1,753.00 kJ/mol
  
25
3rd Energy Level
1,997.00 kJ/mol
  
99+
3,395.00 kJ/mol
  
17
Electrochemical Equivalent
1.77 g/amp-hr
  
39
1.10 g/amp-hr
  
99+
Electron Work Function
Not Available
  
Other Chemical Properties
Density
  
  
Density At Room Temperature
19.38 g/cm3
  
14
8.91 g/cm3
  
99+
Density When Liquid (at m.p.)
Not Available
  
Vapor Pressure
  
  
Vapor Pressure at 1000 K
Not Available
  
Viscosity
Not Available
  
Not Available
  
Elasticity properties
  
  
Shear Modulus
Not Available
  
Bulk Modulus
Not Available
  
Young's Modulus
Not Available
  
Poisson Ratio
Not Available
  
Other Mechanical Properties
Symbol
Np
  
Ni
  
Group Number
Not Available
  
Period Number
7
  
4
  
Atomic Volume
11.62 cm3/mol
  
99+
6.59 cm3/mol
  
99+
Electron Configuration
[Rn] 5f4 6d1 7s2
  
[Ar] 3d8 4s2 Or [Ar] 3d9 4s1
  
Valence Electron Potential
42.00 (-eV)
  
99+
Atom
  
  
Crystal Lattice
ORTH-Crystal-Structure-of-Neptunium.jpg#100
  
FCC-Crystal-Structure-of-Nickel.jpg#100
  
Radius of an Atom
  
  
Lattice Angles
π/2, π/2, π/2
  
π/2, π/2, π/2
  
Lattice C/A Ratio
Not Available
  
Not Available
  
Adjacent Atomic Numbers
  
  
Electrical Properties
  
  
Electrical Conductivity
0.01 106/cm Ω
  
99+
0.14 106/cm Ω
  
13
Electron Affinity
Not Available
  
112.00 kJ/mol
  
6
Magnetic Characteristics
  
  
Magnetic Ordering
Ferromagnetic
  
Permeability
Not Available
  
Susceptibility
Not Available
  
Specific Heat
0.12 J/(kg K)
  
40
0.44 J/(kg K)
  
13
Thermal Conductivity
6.30 W/m·K
  
99+
90.90 W/m·K
  
18
Critical Temperature
Not Available
  
Not Available
  
Molar Heat Capacity
29.46 J/mol·K
  
8
26.07 J/mol·K
  
31
Thermal Expansion
Not Available
  
13.40 µm/(m·K)
  
28
Standard Molar Entropy
Not Available
  
29.90 J/mol.K
  
99+
Enthalpy
  
  
Enthalpy of Vaporization
Not Available
  
371.80 kJ/mol
  
20
Enthalpy of Fusion
3.20 kJ/mol
  
99+
17.57 kJ/mol
  
14
Enthalpy of Atomization
Not Available
  
422.60 kJ/mol
  
17