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Neptunium Rubidium Comparison


Rubidium Neptunium comparison


Periodic Table

Symbol
Np   
Rb   

Group Number
Not Available   
1   
17

Period Number
7   
5   

Block
f block   
s block   

Element Family
Actinide   
Alkali   

CAS Number
7439998   
99+
7440177   
99+

Space Group Name
Pnma   
Im_ 3m   

Space Group Number
62.00   
11
229.00   
1

Facts

Interesting Facts
Not Available   
  • Rubidium metal is 16th most common element found in the earth crust.
  • Rubidium metal also found in minerals as well as seawater.
  

Sources
Made by Bombarding Uranium with Neutrons, Ores of metals   
Obtained from Lithium Production.   

History
  
  

Who Discovered
Edwin McMillan and Philip H. Abelson   
Robert Bunsen and Gustav Kirchhoff   

Discovery
In 1940   
In 1861   

Abundance
  
  

Abundance In Universe
Not Available   
1 * 10-6 %   
16

Abundance In Sun
~-9999 %   
~0.000003 %   
17

Abundance In Meteorites
Not Available   
0.00 %   
19

Abundance In Earth's Crust
Not Available   
0.01 %   
18

Abundance In Oceans
Not Available   
0.00 %   
7

Abundance In Humans
Not Available   
0.00 %   
7

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.
  
  • Rubidium's main application is in the glass manufacturing.
  • Rubidium can very easily get ionized and hence it is used for ion engines, but it is still less efficient than that of Caesium.
  

Industrial Uses
NA   
NA   

Medical Uses
NA   
NA   

Other Uses
Alloys, Nuclear Research, Research Purposes   
Alloys, Research Purposes   

Biological Properties
  
  

Toxicity
Toxic   
Non Toxic   

Present in Human Body
No   
Yes   

In Blood
0.00 Blood/mg dm-3   
37
2.49 Blood/mg dm-3   
7

In Bone
0.00 p.p.m.   
36
5.00 p.p.m.   
13

Physical Properties

Melting Point
640.00 °C   
99+
38.89 °C   
99+

Boiling Point
3,902.00 °C   
13
688.00 °C   
99+

Appearance
  
  

Physical State
Solid   
Solid   

Color
Silver   
Grayish White   

Luster
Metallic   
NA   

Hardness
  
  

Mohs Hardness
Not Available   
0.30   
24

Brinell Hardness
Not Available   
0.22 MPa   
99+

Speed of Sound
Not Available   
1,300.00 m/s   
99+

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
Np   
Rb   

Isotopes
  
  

Known Isotopes
20   
19
29   
10

Electronegativity
  
  

Pauling Electronegativity
1.36   
29
0.82   
99+

Sanderson Electronegativity
Not Available   
0.31   
32

Allred Rochow Electronegativity
1.22   
26
0.89   
40

Mulliken-Jaffe Electronegativity
Not Available   
0.69   
24

Allen Electronegativity
Not Available   
0.71   
99+

Electropositivity
  
  

Pauling Electropositivity
2.64   
25
3.18   
3

Ionization Energies
  
  

1st Energy Level
604.50 kJ/mol   
99+
403.00 kJ/mol   
99+

2nd Energy Level
1,128.00 kJ/mol   
99+
2,633.00 kJ/mol   
6

3rd Energy Level
1,997.00 kJ/mol   
99+
3,860.00 kJ/mol   
11

4th Energy Level
3,242.00 kJ/mol   
99+
5,080.00 kJ/mol   
18

5th Energy Level
Not Available   
6,850.00 kJ/mol   
19

6th Energy Level
Not Available   
8,140.00 kJ/mol   
20

7th Energy level
Not Available   
9,570.00 kJ/mol   
20

8th Energy Level
Not Available   
13,120.00 kJ/mol   
17

9th Energy Level
Not Available   
14,500.00 kJ/mol   
18

10th Energy Level
Not Available   
26,740.00 kJ/mol   
6

Electrochemical Equivalent
1.77 g/amp-hr   
39
3.19 g/amp-hr   
14

Electron Work Function
Not Available   
2.16 eV   
99+

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

Atomic Properties

Atomic Number
93   
25
37   
99+

Electron Configuration
[Rn] 5f4 6d1 7s2   
[Kr] 5s1   

Crystal Structure
Orthorhombic (ORTH)   
Body Centered Cubic (BCC)   

Crystal Lattice
ORTH-Crystal-Structure-of-Neptunium.jpg#100   
BCC-Crystal-Structure-.jpg#100   

Atom
  
  

Number of Protons
93   
25
37   
99+

Number of Neutrons
144   
14
48   
99+

Number of Electrons
93   
25
37   
99+

Radius of an Atom
  
  

Atomic Radius
155.00 pm   
30
248.00 pm   
2

Covalent Radius
190.00 pm   
18
220.00 pm   
4

Van der Waals Radius
221.00 pm   
22
303.00 pm   
3

Atomic Weight
237.00 amu   
22
85.47 amu   
99+

Atomic Volume
11.62 cm3/mol   
99+
55.90 cm3/mol   
2

Adjacent Atomic Numbers
  
  

Previous Element
Uranium
  
Gallium
  

Next Element
Plutonium
  
Strontium
  

Valence Electron Potential
96.00 (-eV)   
9
9.47 (-eV)   
99+

Lattice Constant
666.30 pm   
3
558.50 pm   
10

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
1.53 g/cm3   
99+

Density When Liquid (at m.p.)
Not Available   
1.46 g/cm3   
99+

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
  
  

Bulk Modulus
Not Available   
2.50 GPa   
99+

Young's Modulus
Not Available   
2.40 GPa   
99+

Poisson Ratio
Not Available   
Not Available   

Other Mechanical Properties
Ductile   
Ductile   

Magnetic Properties

Magnetic Characteristics
  
  

Specific Gravity
20.25   
6
1.53   
99+

Magnetic Ordering
Paramagnetic   
Paramagnetic   

Electrical Properties
  
  

Electrical Property
Conductor   
Conductor   

Resistivity
1.22 nΩ·m   
99+
128.00 nΩ·m   
26

Electrical Conductivity
0.01 106/cm Ω   
99+
0.08 106/cm Ω   
24

Electron Affinity
Not Available   
46.90 kJ/mol   
24

Thermal Properties

Specific Heat
0.12 J/(kg K)   
40
0.36 J/(kg K)   
17

Molar Heat Capacity
29.46 J/mol·K   
8
31.06 J/mol·K   
5

Thermal Conductivity
6.30 W/m·K   
99+
58.20 W/m·K   
26

Critical Temperature
Not Available   
2,093.00 K   
4

Thermal Expansion
Not Available   
90.00 µm/(m·K)   
2

Enthalpy
  
  

Enthalpy of Vaporization
Not Available   
69.20 kJ/mol   
99+

Enthalpy of Fusion
3.20 kJ/mol   
99+
2.19 kJ/mol   
99+

Enthalpy of Atomization
Not Available   
82.00 kJ/mol   
99+

Standard Molar Entropy
Not Available   
76.80 J/mol.K   
5

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