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Promethium Thallium Comparison


Thallium Promethium comparison


Periodic Table

Symbol
Pm   
Tl   

Group Number
Not Available   
13   
5

Period Number
6   
6   

Block
f block   
p block   

Element Family
Lanthanide   
Post-​Transition   

CAS Number
7440122   
99+
7440280   
99+

Space Group Name
Not Available   
P63/mmc   

Space Group Number
Not Available   
194.00   
5

Facts

Interesting Facts
  • Promethium metal found in Pitchblende.
  • Promethium metal is highly radioactive metal.
  
  • Compounds of Thallium metal are highly Toxic.
  • Thallium metal is being suspected as a human carcinogen.
  

Sources
Found in Minerals, Mining   
Found As a By-product, Ores of metals, Ores of Minerals   

History
  
  

Who Discovered
Chien Shiung Wu, Emilio Segrè, Hans Bethe   
William Crookes   

Discovery
In 1942   
In 1861   

Abundance
  
  

Abundance In Universe
Not Available   
5 * 10-9 %   
32

Abundance In Sun
~-9999 %   
~0.0000001 %   
26

Abundance In Meteorites
Not Available   
0.00 %   
99+

Abundance In Earth's Crust
Not Available   
0.00 %   
99+

Abundance In Oceans
Not Available   
0.00 %   
34

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.
  
  • Thallium is a toxic metal and hence it has limited uses. Thallium metal is mostly used for producing photoelectric cells.
  • In thermometer’s mercury alloy has 8% of thallium, as it has a melting point lower than 20°C.
  

Industrial Uses
NA   
Chemical Industry   

Medical Uses
NA   
Medical Research   

Other Uses
NA   
Alloys   

Biological Properties
  
  

Toxicity
Non Toxic   
Highly Toxic   

Present in Human Body
No   
Yes   

In Blood
0.00 Blood/mg dm-3   
37
0.00 Blood/mg dm-3   
34

In Bone
Not Available   
0.00 p.p.m.   
33

Physical Properties

Melting Point
1,042.00 °C   
99+
303.50 °C   
99+

Boiling Point
3,000.00 °C   
31
1,457.00 °C   
99+

Appearance
  
  

Physical State
Solid   
Solid   

Color
Unknown   
Silvery White   

Luster
Metallic   
NA   

Hardness
  
  

Mohs Hardness
Not Available   
1.20   
20

Brinell Hardness
Not Available   
26.50 MPa   
99+

Speed of Sound
Not Available   
818.00 m/s   
99+

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
Pm   
Tl   

Isotopes
  
  

Known Isotopes
27   
12
32   
7

Electronegativity
  
  

Pauling Electronegativity
Not Available   
1.62   
21

Sanderson Electronegativity
Not Available   
2.25   
5

Allred Rochow Electronegativity
1.07   
32
1.44   
17

Mulliken-Jaffe Electronegativity
Not Available   
1.96   
6

Allen Electronegativity
Not Available   
1.79   
13

Electropositivity
  
  

Pauling Electropositivity
Not Available   
2.38   
33

Ionization Energies
  
  

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

2nd Energy Level
1,050.00 kJ/mol   
99+
1,971.00 kJ/mol   
14

3rd Energy Level
2,150.00 kJ/mol   
99+
2,878.00 kJ/mol   
32

4th Energy Level
3,970.00 kJ/mol   
38
Not Available   

Electrochemical Equivalent
1.80 g/amp-hr   
36
7.63 g/amp-hr   
2

Electron Work Function
Not Available   
3.84 eV   
28

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

Atomic Properties

Atomic Number
61   
99+
81   
35

Electron Configuration
[Xe] 4f5 6s2   
[Xe] 4f14 5d10 6s2 6p1   

Crystal Structure
Double Hexagonal Close Packed (DHCP)   
Hexagonal Close Packed (HCP)   

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

Atom
  
  

Number of Protons
61   
99+
81   
35

Number of Neutrons
84   
40
123   
20

Number of Electrons
61   
99+
81   
35

Radius of an Atom
  
  

Atomic Radius
183.00 pm   
10
170.00 pm   
22

Covalent Radius
199.00 pm   
12
145.00 pm   
39

Van der Waals Radius
236.00 pm   
16
196.00 pm   
30

Atomic Weight
145.00 amu   
99+
204.38 amu   
31

Atomic Volume
22.39 cm3/mol   
12
17.20 cm3/mol   
31

Adjacent Atomic Numbers
  
  

Previous Element
Neodymium
  
Mercury
  

Next Element
Samarium
  
Lead
  

Valence Electron Potential
44.10 (-eV)   
39
9.60 (-eV)   
99+

Lattice Constant
Not Available   
345.66 pm   
99+

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

Lattice C/A Ratio
Not Available   
1.60   
6

Mechanical Properties

Density
  
  

Density At Room Temperature
7.26 g/cm3   
99+
11.85 g/cm3   
31

Density When Liquid (at m.p.)
Not Available   
11.22 g/cm3   
13

Tensile Strength
Not Available   
Not Available   

Viscosity
Not Available   
Not Available   

Vapor Pressure
  
  

Vapor Pressure at 1000 K
Not Available   
16.90 (Pa)   
5

Elasticity properties
  
  

Shear Modulus
18.00 GPa   
36
2.80 GPa   
99+

Bulk Modulus
33.00 GPa   
36
43.00 GPa   
28

Young's Modulus
46.00 GPa   
38
8.00 GPa   
99+

Poisson Ratio
0.28   
17
0.45   
2

Other Mechanical Properties
NA   
Ductile, Sectile   

Magnetic Properties

Magnetic Characteristics
  
  

Specific Gravity
7.26   
99+
11.85   
22

Magnetic Ordering
Paramagnetic   
Diamagnetic   

Electrical Properties
  
  

Electrical Property
Conductor   
Conductor   

Resistivity
0.75 nΩ·m   
99+
0.18 nΩ·m   
99+

Electrical Conductivity
Not Available   
0.06 106/cm Ω   
32

Electron Affinity
50.00 kJ/mol   
21
19.20 kJ/mol   
32

Thermal Properties

Specific Heat
0.18 J/(kg K)   
33
0.13 J/(kg K)   
39

Molar Heat Capacity
Not Available   
26.32 J/mol·K   
29

Thermal Conductivity
17.90 W/m·K   
99+
46.10 W/m·K   
33

Critical Temperature
Not Available   
Not Available   

Thermal Expansion
9.00 µm/(m·K)   
99+
29.90 µm/(m·K)   
12

Enthalpy
  
  

Enthalpy of Vaporization
Not Available   
162.10 kJ/mol   
99+

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

Enthalpy of Atomization
310.00 kJ/mol   
34
179.90 kJ/mol   
99+

Standard Molar Entropy
Not Available   
64.20 J/mol.K   
19

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