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Neptunium vs Polonium

Neptunium
Polonium
Polonium vs Neptunium


Periodic Table
Symbol
Np   
Po   
Group Number
Not Available   
16   
2
Period Number
7   
6   
Block
f block   
p block   
Element Family
Actinide   
Post-​Transition   
CAS Number
7439998   
99+
7440086   
99+
Space Group Name
Pnma   
Pm-3m   
Space Group Number
62.00   
11
221.00   
3
Facts
Interesting Facts
Not Available   
  • Polonium was the first radioactive element to be discovered.
  • Polonium element and its compounds are highly radioactive.
  • Its alloy with Beryllium provides source of neutrons.
  
Sources
Made by Bombarding Uranium with Neutrons, Ores of metals   
Mining, Ores of metals   
History
  
  
Who Discovered
Edwin McMillan and Philip H. Abelson   
Pierre Curie and Marie Curie   
Discovery
In 1940   
In 1898   
Abundance
  
  
Abundance In Oceans
Not Available   
0.00 %   
99+
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.
  
  • Polonium metal has different Allotropes, it is used in antistatic devices and for research purpose.
  • A 1 gram of Polonium can reach a temperature of 500°C, hence it is used as a heat source for space equipment.
  
Industrial Uses
NA   
Aerospace Industry, Ammunition Industry   
Medical Uses
NA   
NA   
Other Uses
Alloys, Nuclear Research, Research Purposes   
Alloys   
Biological Properties
  
  
Toxicity
Toxic   
Highly Toxic   
Present in Human Body
No   
No   
In Blood
0.00 Blood/mg dm-3   
37
0.00 Blood/mg dm-3   
37
In Bone
0.00 p.p.m.   
36
0.00 p.p.m.   
36
Physical Properties
Melting Point
640.00 °C   
99+
254.00 °C   
99+
Boiling Point
3,902.00 °C   
13
962.00 °C   
99+
Appearance
  
  
Physical State
Solid   
Solid   
Color
Silver   
Silver   
Luster
Metallic   
NA   
Hardness
  
  
Speed of Sound
Not Available   
Not Available   
Optical Properties
  
  
Allotropes
No   
Yes   
α Allotropes
Not Available   
α-polonium   
β Allotropes
Not Available   
β-polonium   
γ Allotropes
Not Available   
Not Available   
Chemical Properties
Chemical Formula
Np   
Po   
Isotopes
  
  
Known Isotopes
20   
19
29   
10
Electronegativity
  
  
Pauling Electronegativity
1.36   
29
2.00   
7
Allred Rochow Electronegativity
1.22   
26
1.76   
2
Mulliken-Jaffe Electronegativity
Not Available   
2.48   
1
Allen Electronegativity
Not Available   
2.19   
2
Electropositivity
  
  
Pauling Electropositivity
2.64   
25
2.00   
99+
Ionization Energies
  
  
1st Energy Level
604.50 kJ/mol   
99+
812.10 kJ/mol   
14
2nd Energy Level
1,128.00 kJ/mol   
99+
Not Available   
3rd Energy Level
1,997.00 kJ/mol   
99+
Not Available   
4th Energy Level
3,242.00 kJ/mol   
99+
Not Available   
Electrochemical Equivalent
1.77 g/amp-hr   
39
3.90 g/amp-hr   
8
Electron Work Function
Not Available   
Not Available   
Other Chemical Properties
Ionization, Radioactive Isotopes, Radioactivity, Solubility   
Ionization, Radioactive Isotopes, Solubility   
Atomic Properties
Atomic Number
93   
25
84   
32
Electron Configuration
[Rn] 5f4 6d1 7s2   
[Xe] 4f14 5d10 6s2 6p4   
Crystal Structure
Orthorhombic (ORTH)   
Monoclinic (MON)   
Crystal Lattice
ORTH-Crystal-Structure-of-Neptunium.jpg#100   
MON-Crystal-Structure-of-Polonium.jpg#100   
Atom
  
  
Number of Protons
93   
25
84   
32
Number of Neutrons
144   
14
125   
19
Number of Electrons
93   
25
84   
32
Radius of an Atom
  
  
Atomic Radius
155.00 pm   
30
168.00 pm   
23
Covalent Radius
190.00 pm   
18
140.00 pm   
99+
Van der Waals Radius
221.00 pm   
22
197.00 pm   
29
Atomic Weight
237.00 amu   
22
209.00 amu   
28
Atomic Volume
11.62 cm3/mol   
99+
22.23 cm3/mol   
13
Adjacent Atomic Numbers
  
  
Previous Element
Uranium
  
Bismuth
  
Next Element
Plutonium
  
Francium
  
Valence Electron Potential
96.00 (-eV)   
9
Not Available   
Lattice Constant
666.30 pm   
3
335.90 pm   
99+
Lattice Angles
π/2, π/2, π/2   
π/2, π/2, π/2   
Lattice C/A Ratio
Not Available   
Not Available   
Mechanical Properties
Density
  
  
Density At Room Temperature
19.38 g/cm3   
14
9.20 g/cm3   
99+
Density When Liquid (at m.p.)
Not Available   
9.40 g/cm3   
19
Tensile Strength
125.00 MPa   
14
Not Available   
Viscosity
Not Available   
Not Available   
Vapor Pressure
  
  
Vapor Pressure at 2000 K
0.11 (Pa)   
17
Not Available   
Elasticity properties
  
  
Poisson Ratio
Not Available   
Not Available   
Other Mechanical Properties
Ductile   
NA   
Magnetic Properties
Magnetic Characteristics
  
  
Specific Gravity
20.25   
6
9.32   
31
Magnetic Ordering
Paramagnetic   
Nonmagnetic   
Electrical Properties
  
  
Electrical Property
Conductor   
Conductor   
Resistivity
1.22 nΩ·m   
99+
0.40 nΩ·m   
99+
Electrical Conductivity
0.01 106/cm Ω   
99+
0.02 106/cm Ω   
99+
Electron Affinity
Not Available   
183.30 kJ/mol   
3
Thermal Properties
Specific Heat
0.12 J/(kg K)   
40
0.12 J/(kg K)   
40
Molar Heat Capacity
29.46 J/mol·K   
8
26.40 J/mol·K   
28
Thermal Conductivity
6.30 W/m·K   
99+
20.00 W/m·K   
99+
Critical Temperature
Not Available   
Not Available   
Thermal Expansion
Not Available   
23.50 µm/(m·K)   
16
Enthalpy
  
  
Enthalpy of Vaporization
Not Available   
60.30 kJ/mol   
99+
Enthalpy of Fusion
3.20 kJ/mol   
99+
13.00 kJ/mol   
26
Enthalpy of Atomization
Not Available   
134.00 kJ/mol   
99+
Standard Molar Entropy
Not Available   
Not Available   
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