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Francium vs Hafnium


Hafnium vs Francium


Periodic Table

Symbol
Fr   
Hf   

Group Number
1   
17
4   
14

Period Number
7   
6   

Block
s block   
d block   

Element Family
Alkali   
Transition Metal   

CAS Number
7440735   
18
7440586   
30

Space Group Name
Not Available   
P63/mmc   

Space Group Number
Not Available   
194.00   
5

Facts

Interesting Facts
  • 223 Francium has the longest half life at 21.8.
  • Francium metal is produced by alpha decay in 227Actinium 227.
  
  • Hafnium metal is highly reactive, hence not found free in nature.
  • Hafnium metal as predicated after Mendeleev finished his periodic table.
  

Sources
Formed by Decay Process, Mining   
By-product Zirconium Refining   

History
  
  

Who Discovered
Marguerite Perey   
Dirk Coster and George de Hevesy   

Discovery
In 1939   
In 1922   

Abundance
  
  

Abundance In Universe
Not Available   
7 * 10-8 %   
25

Abundance In Sun
~-9999 %   
~0.0000001 %   
26

Abundance In Meteorites
Not Available   
0.00 %   
37

Abundance In Earth's Crust
Not Available   
0.00 %   
31

Abundance In Oceans
Not Available   
0.00 %   
27

Uses

Uses & Benefits
  • Francium has no known uses as it has a half life of only 22 minutes.
  
  • It has an ability to absorb neutrons and hence it is used to make control rods in nuclear submarines. And this metal is also used in Plasma welding torches.
  • It alloys with iron, titanium and niobium are very useful.
  

Industrial Uses
NA   
Ammunition Industry   

Medical Uses
NA   
NA   

Other Uses
NA   
Alloys, In Nuclear Reactors, Nuclear Research, Research Purposes   

Biological Properties
  
  

Toxicity
NA   
Toxic   

Present in Human Body
No   
No   

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

In Bone
0.00 p.p.m.   
36
Not Available   

Physical Properties

Melting Point
27.00 °C   
99+
2,150.00 °C   
10

Boiling Point
677.00 °C   
99+
5,400.00 °C   
5

Appearance
  
  

Physical State
Solid   
Solid   

Color
NA   
Gray   

Luster
NA   
Metallic   

Hardness
  
  

Mohs Hardness
Not Available   
5.50   
7

Brinell Hardness
Not Available   
1,450.00 MPa   
6

Vickers Hardness
Not Available   
1,520.00 MPa   
5

Speed of Sound
Not Available   
3,010.00 m/s   
27

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
Fr   
Hf   

Isotopes
  
  

Known Isotopes
33   
6
32   
7

Electronegativity
  
  

Pauling Electronegativity
0.70   
99+
1.30   
32

Allred Rochow Electronegativity
0.86   
99+
1.23   
25

Mulliken-Jaffe Electronegativity
0.68   
25
Not Available   

Allen Electronegativity
0.67   
99+
1.16   
37

Electropositivity
  
  

Pauling Electropositivity
3.30   
1
2.70   
22

Ionization Energies
  
  

1st Energy Level
380.00 kJ/mol   
99+
658.50 kJ/mol   
40

2nd Energy Level
Not Available   
1,440.00 kJ/mol   
99+

3rd Energy Level
Not Available   
2,250.00 kJ/mol   
99+

4th Energy Level
Not Available   
3,216.00 kJ/mol   
99+

Electrochemical Equivalent
8.32 g/amp-hr   
1
1.66 g/amp-hr   
99+

Electron Work Function
Not Available   
3.90 eV   
27

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

Atomic Properties

Atomic Number
87   
31
72   
99+

Electron Configuration
[Rn] 7s1   
[Xe] 4f14 5d2 6s2   

Crystal Structure
Body Centered Cubic (BCC)   
Hexagonal Close Packed (HCP)   

Crystal Lattice
BCC-Crystal-Structure-.jpg#100   
BCC-Crystal-Structure-.jpg#100   

Atom
  
  

Number of Protons
87   
31
72   
99+

Number of Neutrons
136   
17
106   
29

Number of Electrons
87   
31
72   
99+

Radius of an Atom
  
  

Atomic Radius
Not Available   
159.00 pm   
28

Covalent Radius
260.00 pm   
1
175.00 pm   
23

Van der Waals Radius
348.00 pm   
1
200.00 pm   
28

Atomic Weight
223.00 amu   
27
178.49 amu   
39

Atomic Volume
Not Available   
13.60 cm3/mol   
38

Adjacent Atomic Numbers
  
  

Previous Element
Polonium
  
Lutetium
  

Next Element
Radium
  
Tantalum
  

Valence Electron Potential
8.00 (-eV)   
99+
81.00 (-eV)   
16

Lattice Constant
Not Available   
319.64 pm   
99+

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

Lattice C/A Ratio
Not Available   
1.58   
12

Mechanical Properties

Density
  
  

Density At Room Temperature
1.87 g/cm3   
99+
13.31 g/cm3   
26

Density When Liquid (at m.p.)
Not Available   
12.00 g/cm3   
12

Tensile Strength
Not Available   
445.00 MPa   
8

Viscosity
Not Available   
Not Available   

Vapor Pressure
  
  

Vapor Pressure at 2000 K
Not Available   
0.00 (Pa)   
24

Elasticity properties
  
  

Shear Modulus
Not Available   
30.00 GPa   
23

Bulk Modulus
Not Available   
110.00 GPa   
15

Young's Modulus
Not Available   
78.00 GPa   
25

Poisson Ratio
Not Available   
0.37   
7

Other Mechanical Properties
NA   
Ductile, Malleable   

Magnetic Properties

Magnetic Characteristics
  
  

Specific Gravity
Not Available   
13.31   
18

Magnetic Ordering
Paramagnetic   
Paramagnetic   

Electrical Properties
  
  

Electrical Property
Poor Conductor   
Conductor   

Resistivity
3.00 nΩ·m   
99+
331.00 nΩ·m   
14

Electrical Conductivity
0.03 106/cm Ω   
40
0.03 106/cm Ω   
39

Electron Affinity
Not Available   
0.00 kJ/mol   
40

Thermal Properties

Specific Heat
Not Available   
0.14 J/(kg K)   
37

Molar Heat Capacity
Not Available   
25.73 J/mol·K   
36

Thermal Conductivity
15.00 W/m·K   
99+
23.00 W/m·K   
99+

Critical Temperature
Not Available   
Not Available   

Thermal Expansion
Not Available   
5.90 µm/(m·K)   
99+

Enthalpy
  
  

Enthalpy of Vaporization
Not Available   
661.10 kJ/mol   
5

Enthalpy of Fusion
Not Available   
25.10 kJ/mol   
8

Enthalpy of Atomization
71.00 kJ/mol   
99+
703.00 kJ/mol   
5

Standard Molar Entropy
Not Available   
43.60 J/mol.K   
34

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