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Rubidium vs Neptunium


Neptunium vs Rubidium


Periodic Table

Symbol
Rb   
Np   

Group Number
1   
17
Not Available   

Period Number
5   
7   

Block
s block   
f block   

Element Family
Alkali   
Actinide   

CAS Number
7440177   
99+
7439998   
99+

Space Group Name
Im_ 3m   
Pnma   

Space Group Number
229.00   
1
62.00   
11

Facts

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

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

History
  
  

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

Discovery
In 1861   
In 1940   

Abundance
  
  

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

Abundance In Sun
~0.000003 %   
17
~-9999 %   

Abundance In Meteorites
0.00 %   
19
Not Available   

Abundance In Earth's Crust
0.01 %   
18
Not Available   

Abundance In Oceans
0.00 %   
7
Not Available   

Abundance In Humans
0.00 %   
7
Not Available   

Uses

Uses & Benefits
  • 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.
  
  • 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
NA   
NA   

Medical Uses
NA   
NA   

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

Biological Properties
  
  

Toxicity
Non Toxic   
Toxic   

Present in Human Body
Yes   
No   

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

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

Physical Properties

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

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

Appearance
  
  

Physical State
Solid   
Solid   

Color
Grayish White   
Silver   

Luster
NA   
Metallic   

Hardness
  
  

Mohs Hardness
0.30   
24
Not Available   

Brinell Hardness
0.22 MPa   
99+
Not Available   

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

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
Rb   
Np   

Isotopes
  
  

Known Isotopes
29   
10
20   
19

Electronegativity
  
  

Pauling Electronegativity
0.82   
99+
1.36   
29

Sanderson Electronegativity
0.31   
32
Not Available   

Allred Rochow Electronegativity
0.89   
40
1.22   
26

Mulliken-Jaffe Electronegativity
0.69   
24
Not Available   

Allen Electronegativity
0.71   
99+
Not Available   

Electropositivity
  
  

Pauling Electropositivity
3.18   
3
2.64   
25

Ionization Energies
  
  

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

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

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

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

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

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

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

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

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

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

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

Electron Work Function
2.16 eV   
99+
Not Available   

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

Atomic Properties

Atomic Number
37   
99+
93   
25

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

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

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

Atom
  
  

Number of Protons
37   
99+
93   
25

Number of Neutrons
48   
99+
144   
14

Number of Electrons
37   
99+
93   
25

Radius of an Atom
  
  

Atomic Radius
248.00 pm   
2
155.00 pm   
30

Covalent Radius
220.00 pm   
4
190.00 pm   
18

Van der Waals Radius
303.00 pm   
3
221.00 pm   
22

Atomic Weight
85.47 amu   
99+
237.00 amu   
22

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

Adjacent Atomic Numbers
  
  

Previous Element
Gallium
  
Uranium
  

Next Element
Strontium
  
Plutonium
  

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

Lattice Constant
558.50 pm   
10
666.30 pm   
3

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
1.53 g/cm3   
99+
19.38 g/cm3   
14

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

Tensile Strength
Not Available   
125.00 MPa   
14

Viscosity
Not Available   
Not Available   

Vapor Pressure
  
  

Vapor Pressure at 2000 K
Not Available   
0.11 (Pa)   
17

Elasticity properties
  
  

Bulk Modulus
2.50 GPa   
99+
Not Available   

Young's Modulus
2.40 GPa   
99+
Not Available   

Poisson Ratio
Not Available   
Not Available   

Other Mechanical Properties
Ductile   
Ductile   

Magnetic Properties

Magnetic Characteristics
  
  

Specific Gravity
1.53   
99+
20.25   
6

Magnetic Ordering
Paramagnetic   
Paramagnetic   

Electrical Properties
  
  

Electrical Property
Conductor   
Conductor   

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

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

Electron Affinity
46.90 kJ/mol   
24
Not Available   

Thermal Properties

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

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

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

Critical Temperature
2,093.00 K   
4
Not Available   

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

Enthalpy
  
  

Enthalpy of Vaporization
69.20 kJ/mol   
99+
Not Available   

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

Enthalpy of Atomization
82.00 kJ/mol   
99+
Not Available   

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

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