Home
 Compare Metals

Lanthanum vs Promethium

Lanthanum
Promethium
Promethium vs Lanthanum


Periodic Table
Symbol
La  
Pm  
Group Number
3  
15
3  
15
Period Number
6  
6  
Block
f block  
f block  
Element Family
Lanthanide  
Lanthanide  
CAS Number
7439910  
99+
7440122  
99+
Space Group Name
P63/mmc  
-  
Space Group Number
194.00  
7
194.00  
7
Facts
Interesting Facts
  • Lanthanum metal is highly malleable, ductile and sectile.
  • If exposed to air Lanthanum metal oxidizes rapidly.
  
  • Promethium metal found in Pitchblende.
  • Promethium metal is highly radioactive metal.
  
Sources
Found in Minerals, Mining, Ores of Minerals  
Found in Minerals, Mining  
History
  
  
Who Discovered
Carl Gustaf Mosander  
Chien Shiung Wu, Emilio Segrè, Hans Bethe  
Discovery
In 1838  
In 1942  
Abundance
  
  
Abundance In Universe
0.00 %  
23
0.00 %  
40
Abundance In Sun
0.00 %  
25
-  
Abundance In Meteorites
0.00 %  
32
-  
Abundance In Earth's Crust
0.00 %  
19
0.00 %  
99+
Abundance In Oceans
0.00 %  
29
-  
Abundance In Humans
0.00 %  
24
0.00 %  
24
Uses
Uses & Benefits
  • It has no commercial uses, but its alloys are in high demand. Lanthanum and Nickel alloy is used for the hydrogen gas storage.
  • The best-known use for mischmetal alloy of Lanthanum is; as a ‘flints’ for cigarette lighters.
  
  • 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
Electrical Industry, Electronic Industry  
-  
Medical Uses
-  
-  
Other Uses
Alloys, Mirror Manufacturing  
-  
Biological Properties
  
  
Toxicity
Low Toxic  
Non Toxic  
Present in Human Body
Yes  
No  
In Blood
0.00 Blood/mg dm-3  
32
0.00 Blood/mg dm-3  
40
In Bone
0.08 p.p.m.  
29
0.00 p.p.m.  
99+
Physical
Melting Point
920.00 °C  
99+
1,042.00 °C  
99+
Boiling Point
3,469.00 °C  
19
3,000.00 °C  
32
Appearance
  
  
Physical State
Solid  
Solid  
Color
Silvery White  
-  
Luster
-  
Metallic  
Hardness
  
  
Mohs Hardness
2.50  
15
-  
Brinell Hardness
350.00 MPa  
36
400.00 MPa  
34
Vickers Hardness
360.00 MPa  
99+
600.00 MPa  
28
Speed of Sound
2,475.00 m/s  
99+
2,260.00 m/s  
99+
Optical Properties
  
  
Refractive Index
1.80  
22
1.70  
27
Reflectivity
70.00 %  
13
63.00 %  
20
Allotropes
No  
No  
α Allotropes
-  
-  
β Allotropes
-  
-  
γ Allotropes
-  
-  
Chemical
Chemical Formula
La  
Pm  
Isotopes
  
  
Known Isotopes
31  
8
27  
12
Electronegativity
  
  
Pauling Electronegativity
1.10  
99+
1.13  
99+
Sanderson Electronegativity
1.10  
38
1.13  
36
Allred Rochow Electronegativity
1.08  
32
1.07  
33
Mulliken-Jaffe Electronegativity
1.10  
99+
1.13  
99+
Allen Electronegativity
1.10  
99+
1.13  
99+
Electropositivity
  
  
Pauling Electropositivity
2.90  
10
2.20  
39
Ionization Energies
  
  
1st Energy Level
538.10 kJ/mol  
99+
540.00 kJ/mol  
99+
2nd Energy Level
1,067.00 kJ/mol  
99+
1,050.00 kJ/mol  
99+
3rd Energy Level
1,850.30 kJ/mol  
99+
2,150.00 kJ/mol  
99+
4th Energy Level
4,819.00 kJ/mol  
32
3,970.00 kJ/mol  
99+
5th Energy Level
5,940.00 kJ/mol  
99+
5,400.00 kJ/mol  
99+
6th Energy Level
5,380.00 kJ/mol  
99+
5,400.00 kJ/mol  
99+
7th Energy level
5,380.00 kJ/mol  
99+
5,400.00 kJ/mol  
99+
8th Energy Level
5,380.00 kJ/mol  
99+
5,400.00 kJ/mol  
99+
9th Energy Level
5,380.00 kJ/mol  
99+
5,400.00 kJ/mol  
99+
10th Energy Level
5,380.00 kJ/mol  
99+
5,400.00 kJ/mol  
99+
11th Energy Level
5,380.00 kJ/mol  
99+
5,400.00 kJ/mol  
99+
12th Energy Level
5,380.00 kJ/mol  
99+
5,400.00 kJ/mol  
99+
13th Energy Level
5,380.00 kJ/mol  
99+
5,400.00 kJ/mol  
99+
14th Energy Level
5,380.00 kJ/mol  
99+
5,400.00 kJ/mol  
99+
15th Energy Level
53,800.00 kJ/mol  
99+
54,000.00 kJ/mol  
99+
16th Energy Level
53,800.00 kJ/mol  
99+
54,000.00 kJ/mol  
99+
17th Energy Level
538.10 kJ/mol  
99+
540.50 kJ/mol  
99+
18th Energy Level
5,380.00 kJ/mol  
99+
5,400.00 kJ/mol  
99+
19th Energy Level
538.10 kJ/mol  
99+
540.00 kJ/mol  
99+
20th Energy Level
538.00 kJ/mol  
99+
540.00 kJ/mol  
99+
21st Energy Level
538.10 kJ/mol  
99+
540.00 kJ/mol  
99+
22nd Energy Level
538.00 kJ/mol  
99+
540.00 kJ/mol  
99+
23rd Energy Level
5,380.00 kJ/mol  
25
540.00 kJ/mol  
99+
24th Energy Level
538.00 kJ/mol  
99+
540.00 kJ/mol  
99+
25th Energy Level
538.00 kJ/mol  
99+
540.00 kJ/mol  
99+
26th Energy Level
538.00 kJ/mol  
99+
540.00 kJ/mol  
99+
27th Energy Level
538.10 kJ/mol  
99+
540.00 kJ/mol  
99+
28th Energy Level
538.00 kJ/mol  
99+
540.00 kJ/mol  
99+
29th Energy Level
538.10 kJ/mol  
99+
540.00 kJ/mol  
99+
30th Energy Level
538.00 kJ/mol  
99+
540.00 kJ/mol  
99+
Electrochemical Equivalent
1.73 g/amp-hr  
99+
1.80 g/amp-hr  
40
Electron Work Function
3.50 eV  
99+
5.30 eV  
5
Other Chemical Properties
Ionization, Radioactive Isotopes, Solubility  
Ionization, Radioactive Isotopes, Solubility  
Atomic
Atomic Number
57  
99+
61  
99+
Electron Configuration
[Xe] 5d2 6s2  
[Xe] 4f5 6s2  
Crystal Structure
Double Hexagonal Close Packed (DHCP)  
Double Hexagonal Close Packed (DHCP)  
Crystal Lattice
DHCP-Crystal-Structure-of-Lanthanum.jpg#100  
DHCP-Crystal-Structure-of-Promethium.jpg#100  
Atom
  
  
Number of Protons
57  
99+
61  
99+
Number of Neutrons
82  
99+
84  
99+
Number of Electrons
57  
99+
61  
99+
Radius of an Atom
  
  
Atomic Radius
187.00 pm  
10
183.00 pm  
12
Covalent Radius
207.00 pm  
6
199.00 pm  
12
Van der Waals Radius
240.00 pm  
17
236.00 pm  
20
Atomic Weight
138.91 amu  
99+
145.00 amu  
99+
Atomic Volume
20.73 cm3/mol  
26
22.39 cm3/mol  
21
Adjacent Atomic Numbers
  
  
Previous Element
Barium
  
Neodymium
  
Next Element
Cerium
  
Samarium
  
Valence Electron Potential
40.71 (-eV)  
99+
44.10 (-eV)  
40
Lattice Constant
377.20 pm  
31
-  
Lattice Angles
π/2, π/2, 2 π/3  
-  
Lattice C/A Ratio
1.62  
16
1.63  
14
Mechanical
Density
  
  
Density At Room Temperature
6.16 g/cm3  
99+
7.26 g/cm3  
99+
Density When Liquid (at m.p.)
5.94 g/cm3  
99+
7.26 g/cm3  
99+
Tensile Strength
45.00 MPa  
40
75.00 MPa  
30
Viscosity
0.00  
25
0.00  
25
Vapor Pressure
  
  
Vapor Pressure at 1000 K
0.00 (Pa)  
22
0.00 (Pa)  
37
Vapor Pressure at 2000 K
0.98 (Pa)  
15
0.00 (Pa)  
31
Elasticity properties
  
  
Shear Modulus
14.30 GPa  
99+
18.00 GPa  
99+
Bulk Modulus
27.90 GPa  
99+
33.00 GPa  
99+
Young's Modulus
36.60 GPa  
99+
46.00 GPa  
99+
Poisson Ratio
0.28  
17
0.28  
17
Other Mechanical Properties
Ductile  
-  
Magnetic
Magnetic Characteristics
  
  
Specific Gravity
6.17  
99+
7.26  
99+
Magnetic Ordering
Paramagnetic  
Paramagnetic  
Permeability
0.00 H/m  
15
0.00 H/m  
11
Susceptibility
0.00  
25
0.00  
25
Electrical Properties
  
  
Electrical Property
Conductor  
Conductor  
Resistivity
615.00 nΩ·m  
7
0.75 nΩ·m  
99+
Electrical Conductivity
0.01 106/cm Ω  
99+
0.00 106/cm Ω  
99+
Electron Affinity
48.00 kJ/mol  
28
50.00 kJ/mol  
26
Thermal
Specific Heat
0.19 J/(kg K)  
33
0.18 J/(kg K)  
34
Molar Heat Capacity
27.11 J/mol·K  
27
27.60 J/mol·K  
20
Thermal Conductivity
13.40 W/m·K  
99+
17.90 W/m·K  
99+
Critical Temperature
1,193.00 K  
99+
1,315.00 K  
99+
Thermal Expansion
12.10 µm/(m·K)  
99+
9.00 µm/(m·K)  
99+
Enthalpy
  
  
Enthalpy of Vaporization
399.60 kJ/mol  
24
289.00 kJ/mol  
99+
Enthalpy of Fusion
6.20 kJ/mol  
99+
7.50 kJ/mol  
99+
Enthalpy of Atomization
431.00 kJ/mol  
21
310.00 kJ/mol  
99+
Standard Molar Entropy
56.90 J/mol.K  
31
57.00 J/mol.K  
30
Periodic Table >>
<< All

Compare Lanthanide Series

Lanthanide Series

Lanthanide Series

» More Lanthanide Series

Compare Lanthanide Series

» More Compare Lanthanide Series
Home | About | Contact | Disclaimer | Terms of use
© A softusvista inc. venture!