Home
Compare Metals


Polonium vs Lanthanum


Lanthanum vs Polonium


Periodic Table

Symbol
Po   
La   

Group Number
16   
2
Not Available   

Period Number
6   
6   

Block
p block   
f block   

Element Family
Post-​Transition   
Lanthanide   

CAS Number
7440086   
99+
7439910   
99+

Space Group Name
Pm-3m   
P63/mmc   

Space Group Number
221.00   
3
194.00   
5

Facts

Interesting Facts
  • Polonium was the first radioactive element to be discovered.
  • Polonium element and its compounds are highly radioactive.
  • Its alloy with Beryllium provides source of neutrons.
  
  • Lanthanum metal is highly malleable, ductile and sectile.
  • If exposed to air Lanthanum metal oxidizes rapidly.
  

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

History
  
  

Who Discovered
Pierre Curie and Marie Curie   
Carl Gustaf Mosander   

Discovery
In 1898   
In 1838   

Abundance
  
  

Abundance In Universe
Not Available   
2 * 10-7 %   
22

Abundance In Sun
~-9999 %   
~0.0000002 %   
25

Abundance In Meteorites
Not Available   
0.00 %   
32

Abundance In Earth's Crust
Not Available   
0.00 %   
19

Abundance In Oceans
0.00 %   
99+
0.00 %   
29

Uses

Uses & Benefits
  • Polonium metal has different Allotropes, it is used in antistatic devices and for research purpose.
  • A 1 gram of Polonium can reach a temperature of 500°C, hence it is used as a heat source for space equipment.
  
  • 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.
  

Industrial Uses
Aerospace Industry, Ammunition Industry   
Electrical Industry, Electronic Industry   

Medical Uses
NA   
NA   

Other Uses
Alloys   
Alloys, Mirror Manufacturing   

Biological Properties
  
  

Toxicity
Highly Toxic   
Low Toxic   

Present in Human Body
No   
Yes   

In Blood
0.00 Blood/mg dm-3   
37
Not Available   

In Bone
0.00 p.p.m.   
36
0.08 p.p.m.   
24

Physical Properties

Melting Point
254.00 °C   
99+
920.00 °C   
99+

Boiling Point
962.00 °C   
99+
3,469.00 °C   
18

Appearance
  
  

Physical State
Solid   
Solid   

Color
Silver   
Silvery White   

Luster
NA   
NA   

Hardness
  
  

Mohs Hardness
Not Available   
2.50   
14

Brinell Hardness
Not Available   
350.00 MPa   
30

Vickers Hardness
Not Available   
360.00 MPa   
26

Speed of Sound
Not Available   
2,475.00 m/s   
37

Optical Properties
  
  

Allotropes
Yes   
No   

α Allotropes
α-polonium   
Not Available   

β Allotropes
β-polonium   
Not Available   

γ Allotropes
Not Available   
Not Available   

Chemical Properties

Chemical Formula
Po   
La   

Isotopes
  
  

Known Isotopes
29   
10
31   
8

Electronegativity
  
  

Pauling Electronegativity
2.00   
7
1.10   
99+

Allred Rochow Electronegativity
1.76   
2
1.08   
31

Mulliken-Jaffe Electronegativity
2.48   
1
Not Available   

Allen Electronegativity
2.19   
2
Not Available   

Electropositivity
  
  

Pauling Electropositivity
2.00   
99+
2.90   
10

Ionization Energies
  
  

1st Energy Level
812.10 kJ/mol   
14
538.10 kJ/mol   
99+

2nd Energy Level
Not Available   
1,067.00 kJ/mol   
99+

3rd Energy Level
Not Available   
1,850.30 kJ/mol   
99+

4th Energy Level
Not Available   
4,819.00 kJ/mol   
22

5th Energy Level
Not Available   
5,940.00 kJ/mol   
25

Electrochemical Equivalent
3.90 g/amp-hr   
8
1.73 g/amp-hr   
99+

Electron Work Function
Not Available   
3.50 eV   
31

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

Atomic Properties

Atomic Number
84   
32
57   
99+

Electron Configuration
[Xe] 4f14 5d10 6s2 6p4   
[Xe] 5d2 6s2   

Crystal Structure
Monoclinic (MON)   
Double Hexagonal Close Packed (DHCP)   

Crystal Lattice
MON-Crystal-Structure-of-Polonium.jpg#100   
DHCP-Crystal-Structure-of-Lanthanum.jpg#100   

Atom
  
  

Number of Protons
84   
32
57   
99+

Number of Neutrons
125   
19
82   
99+

Number of Electrons
84   
32
57   
99+

Radius of an Atom
  
  

Atomic Radius
168.00 pm   
23
187.00 pm   
8

Covalent Radius
140.00 pm   
99+
207.00 pm   
6

Van der Waals Radius
197.00 pm   
29
240.00 pm   
13

Atomic Weight
209.00 amu   
28
138.91 amu   
99+

Atomic Volume
22.23 cm3/mol   
13
20.73 cm3/mol   
16

Adjacent Atomic Numbers
  
  

Previous Element
Bismuth
  
Barium
  

Next Element
Francium
  
Cerium
  

Valence Electron Potential
Not Available   
40.71 (-eV)   
99+

Lattice Constant
335.90 pm   
99+
377.20 pm   
28

Lattice Angles
π/2, π/2, π/2   
π/2, π/2, 2 π/3   

Lattice C/A Ratio
Not Available   
1.62   
2

Mechanical Properties

Density
  
  

Density At Room Temperature
9.20 g/cm3   
99+
6.16 g/cm3   
99+

Density When Liquid (at m.p.)
9.40 g/cm3   
19
5.94 g/cm3   
99+

Tensile Strength
Not Available   
Not Available   

Viscosity
Not Available   
Not Available   

Vapor Pressure
  
  

Vapor Pressure at 2000 K
Not Available   
0.98 (Pa)   
15

Elasticity properties
  
  

Shear Modulus
Not Available   
14.30 GPa   
40

Bulk Modulus
Not Available   
27.90 GPa   
99+

Young's Modulus
Not Available   
36.60 GPa   
99+

Poisson Ratio
Not Available   
0.28   
17

Other Mechanical Properties
NA   
Ductile   

Magnetic Properties

Magnetic Characteristics
  
  

Specific Gravity
9.32   
31
6.17   
99+

Magnetic Ordering
Nonmagnetic   
Paramagnetic   

Electrical Properties
  
  

Electrical Property
Conductor   
Conductor   

Resistivity
0.40 nΩ·m   
99+
615.00 nΩ·m   
7

Electrical Conductivity
0.02 106/cm Ω   
99+
0.01 106/cm Ω   
99+

Electron Affinity
183.30 kJ/mol   
3
48.00 kJ/mol   
23

Thermal Properties

Specific Heat
0.12 J/(kg K)   
40
0.19 J/(kg K)   
32

Molar Heat Capacity
26.40 J/mol·K   
28
27.11 J/mol·K   
21

Thermal Conductivity
20.00 W/m·K   
99+
13.40 W/m·K   
99+

Critical Temperature
Not Available   
Not Available   

Thermal Expansion
23.50 µm/(m·K)   
16
12.10 µm/(m·K)   
32

Enthalpy
  
  

Enthalpy of Vaporization
60.30 kJ/mol   
99+
399.60 kJ/mol   
17

Enthalpy of Fusion
13.00 kJ/mol   
26
6.20 kJ/mol   
99+

Enthalpy of Atomization
134.00 kJ/mol   
99+
431.00 kJ/mol   
16

Standard Molar Entropy
Not Available   
56.90 J/mol.K   
23

Periodic Table >>
<< All

Compare Post Transition Metals

Post-Transition Metals

Post-Transition Metals

» More Post-Transition Metals

Compare Post Transition Metals

» More Compare Post Transition Metals