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Promethium Rubidium Comparison


Rubidium Promethium comparison


Periodic Table

Symbol
Pm  
Rb  

Group Number
3  
15
1  
17

Period Number
6  
5  

Block
f block  
s block  

Element Family
Lanthanide  
Alkali  

CAS Number
7440122  
99+
7440177  
99+

Space Group Name
-  
Im_ 3m  

Space Group Number
194.00  
7
229.00  
2

Facts

Interesting Facts
  • Promethium metal found in Pitchblende.
  • Promethium metal is highly radioactive metal.
  
  • Rubidium metal is 16th most common element found in the earth crust.
  • Rubidium metal also found in minerals as well as seawater.
  

Sources
Found in Minerals, Mining  
Obtained from Lithium Production.  

History
  
  

Who Discovered
Chien Shiung Wu, Emilio Segrè, Hans Bethe  
Robert Bunsen and Gustav Kirchhoff  

Discovery
In 1942  
In 1861  

Abundance
  
  

Abundance In Universe
0.00 %  
40
0.00 %  
17

Abundance In Sun
-  
0.00 %  
17

Abundance In Meteorites
-  
0.00 %  
19

Abundance In Earth's Crust
0.00 %  
99+
0.01 %  
18

Abundance In Oceans
-  
0.00 %  
7

Abundance In Humans
0.00 %  
24
0.00 %  
8

Uses

Uses & Benefits
  • It is used for research purpose. Very small amount of this metal is used in atomic batteries.
  • Its radioactive decay is used for a phosphor to give off light. The light emitted is converted into electricity.
  
  • 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
-  
-  

Medical Uses
-  
-  

Other Uses
-  
Alloys, Research Purposes  

Biological Properties
  
  

Toxicity
Non Toxic  
Non Toxic  

Present in Human Body
No  
Yes  

In Blood
0.00 Blood/mg dm-3  
40
2.49 Blood/mg dm-3  
7

In Bone
0.00 p.p.m.  
99+
5.00 p.p.m.  
13

Physical

Melting Point
1,042.00 °C  
99+
38.89 °C  
99+

Boiling Point
3,000.00 °C  
32
688.00 °C  
99+

Appearance
  
  

Physical State
Solid  
Solid  

Color
-  
Grayish White  

Luster
Metallic  
-  

Hardness
  
  

Mohs Hardness
-  
0.30  
26

Brinell Hardness
400.00 MPa  
34
0.22 MPa  
99+

Vickers Hardness
600.00 MPa  
28
0.22 MPa  
99+

Speed of Sound
2,260.00 m/s  
99+
1,300.00 m/s  
99+

Optical Properties
  
  

Refractive Index
1.70  
27
1.54  
35

Reflectivity
63.00 %  
20
52.00 %  
29

Allotropes
No  
No  

α Allotropes
-  
-  

β Allotropes
-  
-  

γ Allotropes
-  
-  

Chemical

Chemical Formula
Pm  
Rb  

Isotopes
  
  

Known Isotopes
27  
12
29  
10

Electronegativity
  
  

Pauling Electronegativity
1.13  
99+
0.82  
99+

Sanderson Electronegativity
1.13  
36
0.31  
99+

Allred Rochow Electronegativity
1.07  
33
0.89  
99+

Mulliken-Jaffe Electronegativity
1.13  
99+
0.69  
99+

Allen Electronegativity
1.13  
99+
0.71  
99+

Electropositivity
  
  

Pauling Electropositivity
2.20  
39
3.18  
3

Ionization Energies
  
  

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

2nd Energy Level
1,050.00 kJ/mol  
99+
2,633.00 kJ/mol  
6

3rd Energy Level
2,150.00 kJ/mol  
99+
3,860.00 kJ/mol  
11

4th Energy Level
3,970.00 kJ/mol  
99+
5,080.00 kJ/mol  
28

5th Energy Level
5,400.00 kJ/mol  
99+
6,850.00 kJ/mol  
31

6th Energy Level
5,400.00 kJ/mol  
99+
8,140.00 kJ/mol  
31

7th Energy level
5,400.00 kJ/mol  
99+
9,570.00 kJ/mol  
20

8th Energy Level
5,400.00 kJ/mol  
99+
13,120.00 kJ/mol  
17

9th Energy Level
5,400.00 kJ/mol  
99+
14,500.00 kJ/mol  
18

10th Energy Level
5,400.00 kJ/mol  
99+
26,740.00 kJ/mol  
6

11th Energy Level
5,400.00 kJ/mol  
99+
4,030.00 kJ/mol  
99+

12th Energy Level
5,400.00 kJ/mol  
99+
4,030.00 kJ/mol  
99+

13th Energy Level
5,400.00 kJ/mol  
99+
4,030.00 kJ/mol  
99+

14th Energy Level
5,400.00 kJ/mol  
99+
4,030.00 kJ/mol  
99+

15th Energy Level
54,000.00 kJ/mol  
99+
40,300.00 kJ/mol  
99+

16th Energy Level
54,000.00 kJ/mol  
99+
40,300.00 kJ/mol  
99+

17th Energy Level
540.50 kJ/mol  
99+
403.00 kJ/mol  
99+

18th Energy Level
5,400.00 kJ/mol  
99+
4,030.00 kJ/mol  
99+

19th Energy Level
540.00 kJ/mol  
99+
403.00 kJ/mol  
99+

20th Energy Level
540.00 kJ/mol  
99+
403.00 kJ/mol  
99+

21st Energy Level
540.00 kJ/mol  
99+
403.00 kJ/mol  
99+

22nd Energy Level
540.00 kJ/mol  
99+
403.00 kJ/mol  
99+

23rd Energy Level
540.00 kJ/mol  
99+
403.00 kJ/mol  
99+

24th Energy Level
540.00 kJ/mol  
99+
403.00 kJ/mol  
99+

25th Energy Level
540.00 kJ/mol  
99+
403.00 kJ/mol  
99+

26th Energy Level
540.00 kJ/mol  
99+
403.00 kJ/mol  
99+

27th Energy Level
540.00 kJ/mol  
99+
403.00 kJ/mol  
99+

28th Energy Level
540.00 kJ/mol  
99+
403.00 kJ/mol  
99+

29th Energy Level
540.00 kJ/mol  
99+
403.00 kJ/mol  
99+

30th Energy Level
540.00 kJ/mol  
99+
403.00 kJ/mol  
99+

Electrochemical Equivalent
1.80 g/amp-hr  
40
3.19 g/amp-hr  
16

Electron Work Function
5.30 eV  
5
2.16 eV  
99+

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

Atomic

Atomic Number
61  
99+
37  
99+

Electron Configuration
[Xe] 4f5 6s2  
[Kr] 5s1  

Crystal Structure
Double Hexagonal Close Packed (DHCP)  
Body Centered Cubic (BCC)  

Crystal Lattice
DHCP-Crystal-Structure-of-Promethium.jpg#100  
BCC-Crystal-Structure-.jpg#100  

Atom
  
  

Number of Protons
61  
99+
37  
99+

Number of Neutrons
84  
99+
48  
99+

Number of Electrons
61  
99+
37  
99+

Radius of an Atom
  
  

Atomic Radius
183.00 pm  
12
248.00 pm  
3

Covalent Radius
199.00 pm  
12
220.00 pm  
4

Van der Waals Radius
236.00 pm  
20
303.00 pm  
4

Atomic Weight
145.00 amu  
99+
85.47 amu  
99+

Atomic Volume
22.39 cm3/mol  
21
55.90 cm3/mol  
3

Adjacent Atomic Numbers
  
  

Previous Element
Neodymium
  
Gallium
  

Next Element
Samarium
  
Strontium
  

Valence Electron Potential
44.10 (-eV)  
40
9.47 (-eV)  
99+

Lattice Constant
-  
558.50 pm  
11

Lattice Angles
-  
π/2, π/2, π/2  

Lattice C/A Ratio
1.63  
14
1.59  
28

Mechanical

Density
  
  

Density At Room Temperature
7.26 g/cm3  
99+
1.53 g/cm3  
99+

Density When Liquid (at m.p.)
7.26 g/cm3  
99+
1.46 g/cm3  
99+

Tensile Strength
75.00 MPa  
30
30.00 MPa  
99+

Viscosity
0.00  
25
0.00  
23

Vapor Pressure
  
  

Vapor Pressure at 1000 K
0.00 (Pa)  
37
0.00 (Pa)  
37

Vapor Pressure at 2000 K
0.00 (Pa)  
31
0.00 (Pa)  
35

Elasticity properties
  
  

Shear Modulus
18.00 GPa  
99+
2.50 GPa  
99+

Bulk Modulus
33.00 GPa  
99+
2.50 GPa  
99+

Young's Modulus
46.00 GPa  
99+
2.40 GPa  
99+

Poisson Ratio
0.28  
17
0.37  
7

Other Mechanical Properties
-  
Ductile  

Magnetic

Magnetic Characteristics
  
  

Specific Gravity
7.26  
99+
1.53  
99+

Magnetic Ordering
Paramagnetic  
Paramagnetic  

Permeability
0.00 H/m  
11
0.00 H/m  
11

Susceptibility
0.00  
25
0.00  
24

Electrical Properties
  
  

Electrical Property
Conductor  
Conductor  

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

Electrical Conductivity
0.00 106/cm Ω  
99+
0.08 106/cm Ω  
29

Electron Affinity
50.00 kJ/mol  
26
46.90 kJ/mol  
29

Thermal

Specific Heat
0.18 J/(kg K)  
34
0.36 J/(kg K)  
17

Molar Heat Capacity
27.60 J/mol·K  
20
31.06 J/mol·K  
7

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

Critical Temperature
1,315.00 K  
99+
2,093.00 K  
18

Thermal Expansion
9.00 µm/(m·K)  
99+
90.00 µm/(m·K)  
2

Enthalpy
  
  

Enthalpy of Vaporization
289.00 kJ/mol  
99+
69.20 kJ/mol  
99+

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

Enthalpy of Atomization
310.00 kJ/mol  
99+
82.00 kJ/mol  
99+

Standard Molar Entropy
57.00 J/mol.K  
30
76.80 J/mol.K  
5

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