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Chromium vs Promethium


Promethium vs Chromium


Periodic Table

Symbol
Cr  
Pm  

Group Number
6  
12
3  
15

Period Number
4  
6  

Block
d block  
f block  

Element Family
Transition Metal  
Lanthanide  

CAS Number
7440473  
39
7440122  
99+

Space Group Name
Im_ 3m  
-  

Space Group Number
229.00  
2
194.00  
7

Facts

Interesting Facts
  • Chromium is highly reactive, hence it is not found free in nature.
  • Ores of Chromites mineral are the major source of Chromium metal.
  • Almost 90% leather tanning is done with the help of chromium.
  
  • Promethium metal found in Pitchblende.
  • Promethium metal is highly radioactive metal.
  

Sources
Found in Minerals, Mining, Ores of metals, Ores of Minerals  
Found in Minerals, Mining  

History
  
  

Who Discovered
Louis Nicolas Vauquelin  
Chien Shiung Wu, Emilio Segrè, Hans Bethe  

Discovery
In Between 1797 - 1798  
In 1942  

Abundance
  
  

Abundance In Universe
0.00 %  
8
0.00 %  
40

Abundance In Sun
0.00 %  
7
-  

Abundance In Meteorites
0.30 %  
7
-  

Abundance In Earth's Crust
0.01 %  
13
0.00 %  
99+

Abundance In Oceans
0.00 %  
16
-  

Abundance In Humans
0.00 %  
19
0.00 %  
24

Uses

Uses & Benefits
  • It is used to harden the steel and produces a stainless steel and other various alloys.
  • It is also used to give proper finish to polished mirrors. Its chromium plates are used in bathroom fittings.
  
  • 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.
  

Industrial Uses
Automobile Industry, Chemical Industry  
-  

Medical Uses
-  
-  

Other Uses
Alloys  
-  

Biological Properties
  
  

Toxicity
Highly Toxic  
Non Toxic  

Present in Human Body
Yes  
No  

In Blood
0.11 Blood/mg dm-3  
12
0.00 Blood/mg dm-3  
40

In Bone
0.33 p.p.m.  
25
0.00 p.p.m.  
99+

Physical

Melting Point
1,857.00 °C  
14
1,042.00 °C  
99+

Boiling Point
2,672.00 °C  
99+
3,000.00 °C  
32

Appearance
  
  

Physical State
Solid  
Solid  

Color
Silver  
-  

Luster
Metallic  
Metallic  

Hardness
  
  

Mohs Hardness
8.50  
1
-  

Brinell Hardness
687.00 MPa  
18
400.00 MPa  
34

Vickers Hardness
1,060.00 MPa  
17
600.00 MPa  
28

Speed of Sound
5,940.00 m/s  
8
2,260.00 m/s  
99+

Optical Properties
  
  

Refractive Index
2.97  
2
1.70  
27

Reflectivity
70.00 %  
13
63.00 %  
20

Allotropes
No  
No  

α Allotropes
-  
-  

β Allotropes
-  
-  

γ Allotropes
-  
-  

Chemical

Chemical Formula
Cr  
Pm  

Isotopes
  
  

Known Isotopes
21  
18
27  
12

Electronegativity
  
  

Pauling Electronegativity
1.66  
19
1.13  
99+

Sanderson Electronegativity
1.66  
17
1.13  
36

Allred Rochow Electronegativity
1.56  
11
1.07  
33

Mulliken-Jaffe Electronegativity
1.66  
19
1.13  
99+

Allen Electronegativity
1.65  
22
1.13  
99+

Electropositivity
  
  

Pauling Electropositivity
2.34  
36
2.20  
39

Ionization Energies
  
  

1st Energy Level
26,130.00 kJ/mol  
1
540.00 kJ/mol  
99+

2nd Energy Level
28,750.00 kJ/mol  
1
1,050.00 kJ/mol  
99+

3rd Energy Level
34,230.00 kJ/mol  
1
2,150.00 kJ/mol  
99+

4th Energy Level
37,066.00 kJ/mol  
1
3,970.00 kJ/mol  
99+

5th Energy Level
97,510.00 kJ/mol  
1
5,400.00 kJ/mol  
99+

6th Energy Level
105,800.00 kJ/mol  
1
5,400.00 kJ/mol  
99+

7th Energy level
114,300.00 kJ/mol  
1
5,400.00 kJ/mol  
99+

8th Energy Level
125,300.00 kJ/mol  
1
5,400.00 kJ/mol  
99+

9th Energy Level
134,700.00 kJ/mol  
1
5,400.00 kJ/mol  
99+

10th Energy Level
144,300.00 kJ/mol  
1
5,400.00 kJ/mol  
99+

11th Energy Level
26,130.00 kJ/mol  
12
5,400.00 kJ/mol  
99+

12th Energy Level
28,750.00 kJ/mol  
36
5,400.00 kJ/mol  
99+

13th Energy Level
34,230.00 kJ/mol  
10
5,400.00 kJ/mol  
99+

14th Energy Level
37,066.00 kJ/mol  
12
5,400.00 kJ/mol  
99+

15th Energy Level
97,510.00 kJ/mol  
2
54,000.00 kJ/mol  
99+

16th Energy Level
105,800.00 kJ/mol  
2
54,000.00 kJ/mol  
99+

17th Energy Level
114,300.00 kJ/mol  
3
540.50 kJ/mol  
99+

18th Energy Level
125,300.00 kJ/mol  
4
5,400.00 kJ/mol  
99+

19th Energy Level
134,700.00 kJ/mol  
5
540.00 kJ/mol  
99+

20th Energy Level
144,300.00 kJ/mol  
7
540.00 kJ/mol  
99+

21st Energy Level
157,700.00 kJ/mol  
7
540.00 kJ/mol  
99+

22nd Energy Level
166,090.00 kJ/mol  
6
540.00 kJ/mol  
99+

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

24th Energy Level
653.80 kJ/mol  
32
540.00 kJ/mol  
99+

25th Energy Level
653.80 kJ/mol  
34
540.00 kJ/mol  
99+

26th Energy Level
653.80 kJ/mol  
33
540.00 kJ/mol  
99+

27th Energy Level
652.90 kJ/mol  
34
540.00 kJ/mol  
99+

28th Energy Level
653.80 kJ/mol  
39
540.00 kJ/mol  
99+

29th Energy Level
653.80 kJ/mol  
40
540.00 kJ/mol  
99+

30th Energy Level
653.80 kJ/mol  
36
540.00 kJ/mol  
99+

Electrochemical Equivalent
0.32 g/amp-hr  
99+
1.80 g/amp-hr  
40

Electron Work Function
4.50 eV  
19
5.30 eV  
5

Other Chemical Properties
Anti Corrosion, Chemical Stability, Ionization, Radioactive Isotopes, Solubility  
Ionization, Radioactive Isotopes, Solubility  

Atomic

Atomic Number
24  
99+
61  
99+

Electron Configuration
[Ar] 3d5 4s1  
[Xe] 4f5 6s2  

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

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

Atom
  
  

Number of Protons
24  
99+
61  
99+

Number of Neutrons
28  
99+
84  
99+

Number of Electrons
24  
99+
61  
99+

Radius of an Atom
  
  

Atomic Radius
128.00 pm  
99+
183.00 pm  
12

Covalent Radius
139.00 pm  
99+
199.00 pm  
12

Van der Waals Radius
200.00 pm  
35
236.00 pm  
20

Atomic Weight
52.00 amu  
99+
145.00 amu  
99+

Atomic Volume
7.23 cm3/mol  
99+
22.39 cm3/mol  
21

Adjacent Atomic Numbers
  
  

Previous Element
Vanadium
  
Neodymium
  

Next Element
Manganese
  
Samarium
  

Valence Electron Potential
170.00 (-eV)  
4
44.10 (-eV)  
40

Lattice Constant
291.00 pm  
99+
-  

Lattice Angles
π/2, π/2, π/2  
-  

Lattice C/A Ratio
1.86  
4
1.63  
14

Mechanical

Density
  
  

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

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

Tensile Strength
689.00 MPa  
7
75.00 MPa  
30

Viscosity
0.00  
23
0.00  
25

Vapor Pressure
  
  

Vapor Pressure at 1000 K
0.00 (Pa)  
26
0.00 (Pa)  
37

Vapor Pressure at 2000 K
774.00 (Pa)  
1
0.00 (Pa)  
31

Elasticity properties
  
  

Shear Modulus
115.00 GPa  
9
18.00 GPa  
99+

Bulk Modulus
160.00 GPa  
11
33.00 GPa  
99+

Young's Modulus
279.00 GPa  
8
46.00 GPa  
99+

Poisson Ratio
0.21  
33
0.28  
17

Other Mechanical Properties
-  
-  

Magnetic

Magnetic Characteristics
  
  

Specific Gravity
7.19  
99+
7.26  
99+

Magnetic Ordering
Antiferromagnetic  
Paramagnetic  

Permeability
0.00 H/m  
17
0.00 H/m  
11

Susceptibility
0.00  
10
0.00  
25

Electrical Properties
  
  

Electrical Property
-  
Conductor  

Resistivity
125.00 nΩ·m  
27
0.75 nΩ·m  
99+

Electrical Conductivity
0.08 106/cm Ω  
30
0.00 106/cm Ω  
99+

Electron Affinity
64.30 kJ/mol  
17
50.00 kJ/mol  
26

Thermal

Specific Heat
0.45 J/(kg K)  
12
0.18 J/(kg K)  
34

Molar Heat Capacity
23.35 J/mol·K  
99+
27.60 J/mol·K  
20

Thermal Conductivity
93.90 W/m·K  
17
17.90 W/m·K  
99+

Critical Temperature
1,907.00 K  
24
1,315.00 K  
99+

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

Enthalpy
  
  

Enthalpy of Vaporization
348.80 kJ/mol  
35
289.00 kJ/mol  
99+

Enthalpy of Fusion
15.31 kJ/mol  
20
7.50 kJ/mol  
99+

Enthalpy of Atomization
397.50 kJ/mol  
27
310.00 kJ/mol  
99+

Standard Molar Entropy
23.80 J/mol.K  
99+
57.00 J/mol.K  
30

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