Home
Compare Metals


Lead vs Thallium


Thallium vs Lead


Periodic Table

Symbol
Pb   
Tl   

Group Number
14   
4
13   
5

Period Number
6   
6   

Block
p block   
p block   

Element Family
Post-​Transition   
Post-​Transition   

CAS Number
7439921   
99+
7440280   
99+

Space Group Name
Fm_ 3m   
P63/mmc   

Space Group Number
225.00   
2
194.00   
5

Facts

Interesting Facts
  • Galena mineral contains almost 87% of Lead metal in it, Galena is sulfide mineral.
  • The best available source of Lead metal today is by recycling automobile batteries.
  
  • Compounds of Thallium metal are highly Toxic.
  • Thallium metal is being suspected as a human carcinogen.
  

Sources
Earth's crust, Found in Minerals, Mining, Ores of metals, Ores of Minerals   
Found As a By-product, Ores of metals, Ores of Minerals   

History
  
  

Who Discovered
Unknown   
William Crookes   

Discovery
In Middle Easterns (7000 BCE)   
In 1861   

Abundance
  
  

Abundance In Universe
1 * 10-6 %   
16
5 * 10-9 %   
32

Abundance In Sun
~0.000001 %   
18
~0.0000001 %   
26

Abundance In Meteorites
0.00 %   
23
0.00 %   
99+

Abundance In Earth's Crust
0.00 %   
26
0.00 %   
99+

Abundance In Oceans
0.00 %   
22
0.00 %   
34

Abundance In Humans
0.00 %   
8
Not Available   

Uses

Uses & Benefits
  • It is also used in insecticides, hair dyes and as an anti-knocking additive for petrol. But all these are banned by the government as Lead metal is known for detrimental to health.
  
  • 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
Chemical Industry, Electrical Industry, Electronic Industry   
Chemical Industry   

Medical Uses
Surgical Instruments Manufacturing   
Medical Research   

Other Uses
Alloys   
Alloys   

Biological Properties
  
  

Toxicity
Toxic   
Highly Toxic   

Present in Human Body
Yes   
Yes   

In Blood
0.21 Blood/mg dm-3   
11
0.00 Blood/mg dm-3   
34

In Bone
30.00 p.p.m.   
10
0.00 p.p.m.   
33

Physical Properties

Melting Point
327.50 °C   
99+
303.50 °C   
99+

Boiling Point
1,740.00 °C   
99+
1,457.00 °C   
99+

Appearance
  
  

Physical State
Solid   
Solid   

Color
Gray   
Silvery White   

Luster
Metallic   
NA   

Hardness
  
  

Mohs Hardness
1.50   
18
1.20   
20

Brinell Hardness
38.00 MPa   
99+
26.50 MPa   
99+

Speed of Sound
1,190.00 m/s   
99+
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
Pb   
Tl   

Isotopes
  
  

Known Isotopes
35   
4
32   
7

Electronegativity
  
  

Pauling Electronegativity
1.87   
13
1.62   
21

Sanderson Electronegativity
2.29   
4
2.25   
5

Allred Rochow Electronegativity
1.55   
11
1.44   
17

Mulliken-Jaffe Electronegativity
2.41   
2
1.96   
6

Allen Electronegativity
1.85   
8
1.79   
13

Electropositivity
  
  

Pauling Electropositivity
1.67   
99+
2.38   
33

Ionization Energies
  
  

1st Energy Level
715.60 kJ/mol   
31
589.40 kJ/mol   
99+

2nd Energy Level
1,450.50 kJ/mol   
99+
1,971.00 kJ/mol   
14

3rd Energy Level
3,081.50 kJ/mol   
23
2,878.00 kJ/mol   
32

4th Energy Level
4,083.00 kJ/mol   
35
Not Available   

5th Energy Level
6,640.00 kJ/mol   
20
Not Available   

Electrochemical Equivalent
3.87 g/amp-hr   
9
7.63 g/amp-hr   
2

Electron Work Function
4.25 eV   
21
3.84 eV   
28

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

Atomic Properties

Atomic Number
82   
34
81   
35

Electron Configuration
[Xe] 4f14 5d10 6s2 6p2   
[Xe] 4f14 5d10 6s2 6p1   

Crystal Structure
Face Centered Cubic (FCC)   
Hexagonal Close Packed (HCP)   

Crystal Lattice
FCC-Crystal-Structure-of-Lead.jpg#100   
BCC-Crystal-Structure-.jpg#100   

Atom
  
  

Number of Protons
82   
34
81   
35

Number of Neutrons
125   
19
123   
20

Number of Electrons
82   
34
81   
35

Radius of an Atom
  
  

Atomic Radius
175.00 pm   
19
170.00 pm   
22

Covalent Radius
146.00 pm   
38
145.00 pm   
39

Van der Waals Radius
202.00 pm   
27
196.00 pm   
30

Atomic Weight
207.20 amu   
30
204.38 amu   
31

Atomic Volume
18.17 cm3/mol   
27
17.20 cm3/mol   
31

Adjacent Atomic Numbers
  
  

Previous Element
Thallium
  
Mercury
  

Next Element
Bismuth
  
Lead
  

Valence Electron Potential
24.20 (-eV)   
99+
9.60 (-eV)   
99+

Lattice Constant
495.08 pm   
16
345.66 pm   
99+

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

Lattice C/A Ratio
Not Available   
1.60   
6

Mechanical Properties

Density
  
  

Density At Room Temperature
11.34 g/cm3   
33
11.85 g/cm3   
31

Density When Liquid (at m.p.)
10.66 g/cm3   
15
11.22 g/cm3   
13

Tensile Strength
12.00 MPa   
20
Not Available   

Viscosity
Not Available   
Not Available   

Vapor Pressure
  
  

Vapor Pressure at 1000 K
1.64 (Pa)   
7
16.90 (Pa)   
5

Elasticity properties
  
  

Shear Modulus
5.60 GPa   
99+
2.80 GPa   
99+

Bulk Modulus
46.00 GPa   
24
43.00 GPa   
28

Young's Modulus
16.00 GPa   
99+
8.00 GPa   
99+

Poisson Ratio
0.44   
3
0.45   
2

Other Mechanical Properties
Ductile, Malleable   
Ductile, Sectile   

Magnetic Properties

Magnetic Characteristics
  
  

Specific Gravity
11.35   
25
11.85   
22

Magnetic Ordering
Diamagnetic   
Diamagnetic   

Electrical Properties
  
  

Electrical Property
Poor Conductor   
Conductor   

Resistivity
208.00 nΩ·m   
16
0.18 nΩ·m   
99+

Electrical Conductivity
0.05 106/cm Ω   
36
0.06 106/cm Ω   
32

Electron Affinity
35.10 kJ/mol   
28
19.20 kJ/mol   
32

Thermal Properties

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

Molar Heat Capacity
26.65 J/mol·K   
26
26.32 J/mol·K   
29

Thermal Conductivity
35.30 W/m·K   
38
46.10 W/m·K   
33

Critical Temperature
Not Available   
Not Available   

Thermal Expansion
28.90 µm/(m·K)   
13
29.90 µm/(m·K)   
12

Enthalpy
  
  

Enthalpy of Vaporization
179.40 kJ/mol   
99+
162.10 kJ/mol   
99+

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

Enthalpy of Atomization
194.60 kJ/mol   
99+
179.90 kJ/mol   
99+

Standard Molar Entropy
64.80 J/mol.K   
17
64.20 J/mol.K   
19

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