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Lead vs Francium


Francium vs Lead


Periodic Table

Symbol
Pb   
Fr   

Group Number
14   
4
1   
17

Period Number
6   
7   

Block
p block   
s block   

Element Family
Post-​Transition   
Alkali   

CAS Number
7439921   
99+
7440735   
18

Space Group Name
Fm_ 3m   
Not Available   

Space Group Number
225.00   
2
Not Available   

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.
  
  • 223 Francium has the longest half life at 21.8.
  • Francium metal is produced by alpha decay in 227Actinium 227.
  

Sources
Earth's crust, Found in Minerals, Mining, Ores of metals, Ores of Minerals   
Formed by Decay Process, Mining   

History
  
  

Who Discovered
Unknown   
Marguerite Perey   

Discovery
In Middle Easterns (7000 BCE)   
In 1939   

Abundance
  
  

Abundance In Universe
1 * 10-6 %   
16
Not Available   

Abundance In Sun
~0.000001 %   
18
~-9999 %   

Abundance In Meteorites
0.00 %   
23
Not Available   

Abundance In Earth's Crust
0.00 %   
26
Not Available   

Abundance In Oceans
0.00 %   
22
Not Available   

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.
  
  • Francium has no known uses as it has a half life of only 22 minutes.
  

Industrial Uses
Chemical Industry, Electrical Industry, Electronic Industry   
NA   

Medical Uses
Surgical Instruments Manufacturing   
NA   

Other Uses
Alloys   
NA   

Biological Properties
  
  

Toxicity
Toxic   
NA   

Present in Human Body
Yes   
No   

In Blood
0.21 Blood/mg dm-3   
11
0.00 Blood/mg dm-3   
37

In Bone
30.00 p.p.m.   
10
0.00 p.p.m.   
36

Physical Properties

Melting Point
327.50 °C   
99+
27.00 °C   
99+

Boiling Point
1,740.00 °C   
99+
677.00 °C   
99+

Appearance
  
  

Physical State
Solid   
Solid   

Color
Gray   
NA   

Luster
Metallic   
NA   

Hardness
  
  

Mohs Hardness
1.50   
18
Not Available   

Brinell Hardness
38.00 MPa   
99+
Not Available   

Speed of Sound
1,190.00 m/s   
99+
Not Available   

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   
Fr   

Isotopes
  
  

Known Isotopes
35   
4
33   
6

Electronegativity
  
  

Pauling Electronegativity
1.87   
13
0.70   
99+

Sanderson Electronegativity
2.29   
4
Not Available   

Allred Rochow Electronegativity
1.55   
11
0.86   
99+

Mulliken-Jaffe Electronegativity
2.41   
2
0.68   
25

Allen Electronegativity
1.85   
8
0.67   
99+

Electropositivity
  
  

Pauling Electropositivity
1.67   
99+
3.30   
1

Ionization Energies
  
  

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

2nd Energy Level
1,450.50 kJ/mol   
99+
Not Available   

3rd Energy Level
3,081.50 kJ/mol   
23
Not Available   

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
8.32 g/amp-hr   
1

Electron Work Function
4.25 eV   
21
Not Available   

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

Atomic Properties

Atomic Number
82   
34
87   
31

Electron Configuration
[Xe] 4f14 5d10 6s2 6p2   
[Rn] 7s1   

Crystal Structure
Face Centered Cubic (FCC)   
Body Centered Cubic (BCC)   

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

Atom
  
  

Number of Protons
82   
34
87   
31

Number of Neutrons
125   
19
136   
17

Number of Electrons
82   
34
87   
31

Radius of an Atom
  
  

Atomic Radius
175.00 pm   
19
Not Available   

Covalent Radius
146.00 pm   
38
260.00 pm   
1

Van der Waals Radius
202.00 pm   
27
348.00 pm   
1

Atomic Weight
207.20 amu   
30
223.00 amu   
27

Atomic Volume
18.17 cm3/mol   
27
Not Available   

Adjacent Atomic Numbers
  
  

Previous Element
Thallium
  
Polonium
  

Next Element
Bismuth
  
Radium
  

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

Lattice Constant
495.08 pm   
16
Not Available   

Lattice Angles
π/2, π/2, π/2   
NA   

Lattice C/A Ratio
Not Available   
Not Available   

Mechanical Properties

Density
  
  

Density At Room Temperature
11.34 g/cm3   
33
1.87 g/cm3   
99+

Density When Liquid (at m.p.)
10.66 g/cm3   
15
Not Available   

Tensile Strength
12.00 MPa   
20
Not Available   

Viscosity
Not Available   
Not Available   

Vapor Pressure
  
  

Vapor Pressure at 1000 K
1.64 (Pa)   
7
Not Available   

Elasticity properties
  
  

Shear Modulus
5.60 GPa   
99+
Not Available   

Bulk Modulus
46.00 GPa   
24
Not Available   

Young's Modulus
16.00 GPa   
99+
Not Available   

Poisson Ratio
0.44   
3
Not Available   

Other Mechanical Properties
Ductile, Malleable   
NA   

Magnetic Properties

Magnetic Characteristics
  
  

Specific Gravity
11.35   
25
Not Available   

Magnetic Ordering
Diamagnetic   
Paramagnetic   

Electrical Properties
  
  

Electrical Property
Poor Conductor   
Poor Conductor   

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

Electrical Conductivity
0.05 106/cm Ω   
36
0.03 106/cm Ω   
40

Electron Affinity
35.10 kJ/mol   
28
Not Available   

Thermal Properties

Specific Heat
0.13 J/(kg K)   
39
Not Available   

Molar Heat Capacity
26.65 J/mol·K   
26
Not Available   

Thermal Conductivity
35.30 W/m·K   
38
15.00 W/m·K   
99+

Critical Temperature
Not Available   
Not Available   

Thermal Expansion
28.90 µm/(m·K)   
13
Not Available   

Enthalpy
  
  

Enthalpy of Vaporization
179.40 kJ/mol   
99+
Not Available   

Enthalpy of Fusion
4.77 kJ/mol   
99+
Not Available   

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

Standard Molar Entropy
64.80 J/mol.K   
17
Not Available   

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