Symbol
Np
  
Hg
  
Group Number
Not Available
  
Period Number
7
  
6
  
Block
f block
  
d block
  
Element Family
Actinide
  
Transition Metal
  
Space Group Name
Pnma
  
R_ 3m
  
Interesting Facts
Not Available
  
- At room temperature mercury is found in a liquid state.
- A coin of pound or rupees floats in mercury.
- Because of its low melting point and boiling point it is used in thermometers.
  
Sources
Made by Bombarding Uranium with Neutrons, Ores of metals
  
Mining, Ores of Minerals
  
History
  
  
Who Discovered
Edwin McMillan and Philip H. Abelson
  
Ancient Chinese and Indians
  
Discovery
In 1940
  
Before 2000 BCE
  
Abundance
  
  
Abundance In Earth's Crust
Not Available
  
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.
  
- It is a liquid metal at room temperature, but it is a toxic heavy metal and hence many uses of mercury are under review or phased out.
- It is manly used as a catalysts in chemical industry.
  
Industrial Uses
NA
  
Electrical Industry, Electronic Industry
  
Medical Uses
NA
  
Dentistry
  
Other Uses
Alloys, Nuclear Research, Research Purposes
  
Alloys, Mirror Manufacturing, Pharmaceutical Industry
  
Biological Properties
  
  
Toxicity
Toxic
  
Highly Toxic
  
Present in Human Body
No
  
Yes
  
In Blood
0.00 Blood/mg dm-3
  
37
0.01 Blood/mg dm-3
  
23
In Bone
0.00 p.p.m.
  
36
0.45 p.p.m.
  
19
Melting Point
Not Available
  
Boiling Point
3,902.00 °C
  
13
Appearance
  
  
Physical State
Solid
  
Liquid
  
Color
Silver
  
Silver
  
Luster
Metallic
  
NA
  
Hardness
  
  
Speed of Sound
Not Available
  
1,451.40 m/s
  
99+
Optical Properties
  
  
Refractive Index
Not Available
  
Reflectivity
Not Available
  
Allotropes
No
  
No
  
α Allotropes
Not Available
  
Not Available
  
β Allotropes
Not Available
  
Not Available
  
γ Allotropes
Not Available
  
Not Available
  
Chemical Formula
Np
  
Hg
  
Isotopes
  
  
Electronegativity
  
  
Pauling Electronegativity
Sanderson Electronegativity
Not Available
  
Allred Rochow Electronegativity
Mulliken-Jaffe Electronegativity
Not Available
  
Allen Electronegativity
Not Available
  
Electropositivity
  
  
Pauling Electropositivity
Ionization Energies
  
  
1st Energy Level
604.50 kJ/mol
  
99+
1,007.10 kJ/mol
  
4
2nd Energy Level
1,128.00 kJ/mol
  
99+
1,810.00 kJ/mol
  
20
3rd Energy Level
1,997.00 kJ/mol
  
99+
3,300.00 kJ/mol
  
20
4th Energy Level
3,242.00 kJ/mol
  
99+
Not Available
  
Electrochemical Equivalent
1.77 g/amp-hr
  
39
3.74 g/amp-hr
  
10
Electron Work Function
Not Available
  
Other Chemical Properties
Ionization, Radioactive Isotopes, Radioactivity, Solubility
  
Flammability, Ionization, Solubility
  
Electron Configuration
[Rn] 5f4 6d1 7s2
  
[Xe] 4f14 5d10 6s2
  
Crystal Structure
Orthorhombic (ORTH)
  
Rhombohedral (RHO)
  
Crystal Lattice
ORTH-Crystal-Structure-of-Neptunium.jpg#100
  
RHO-Crystal-Structure-of-Mercury.jpg#100
  
Atom
  
  
Radius of an Atom
  
  
Atomic Volume
11.62 cm3/mol
  
99+
14.82 cm3/mol
  
35
Adjacent Atomic Numbers
  
  
Valence Electron Potential
28.20 (-eV)
  
99+
Lattice Angles
π/2, π/2, π/2
  
NA
  
Lattice C/A Ratio
Not Available
  
Not Available
  
Density
  
  
Density At Room Temperature
19.38 g/cm3
  
14
13.53 g/cm3
  
24
Tensile Strength
Not Available
  
Viscosity
Not Available
  
Vapor Pressure
  
  
Vapor Pressure at 2000 K
Not Available
  
Elasticity properties
  
  
Poisson Ratio
Not Available
  
Not Available
  
Other Mechanical Properties
Ductile
  
NA
  
Magnetic Characteristics
  
  
Magnetic Ordering
Paramagnetic
  
Diamagnetic
  
Electrical Properties
  
  
Electrical Property
Conductor
  
Conductor
  
Electrical Conductivity
0.01 106/cm Ω
  
99+
0.01 106/cm Ω
  
99+
Electron Affinity
Not Available
  
0.00 kJ/mol
  
40
Specific Heat
0.12 J/(kg K)
  
40
0.14 J/(kg K)
  
38
Molar Heat Capacity
29.46 J/mol·K
  
8
27.98 J/mol·K
  
13
Thermal Conductivity
6.30 W/m·K
  
99+
8.30 W/m·K
  
99+
Critical Temperature
Not Available
  
Thermal Expansion
Not Available
  
60.40 µm/(m·K)
  
5
Enthalpy
  
  
Enthalpy of Vaporization
Not Available
  
56.90 kJ/mol
  
99+
Enthalpy of Fusion
3.20 kJ/mol
  
99+
2.29 kJ/mol
  
99+
Enthalpy of Atomization
Not Available
  
61.50 kJ/mol
  
99+
Standard Molar Entropy
Not Available
  
75.80 J/mol.K
  
6