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Francium Erbium Comparison


Erbium Francium comparison


Periodic Table

Symbol
Fr   
Er   

Group Number
1   
17
Not Available   

Period Number
7   
6   

Block
s block   
f block   

Element Family
Alkali   
Lanthanide   

CAS Number
7440735   
18
7440520   
35

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.
  
  • Erbium metal is used as alloyed with Vanadium to make it softer.
  • Recent studies shows that it is helpful for metabolism.
  

Sources
Formed by Decay Process, Mining   
Mining   

History
  
  

Who Discovered
Marguerite Perey   
Carl Gustaf Mosander   

Discovery
In 1939   
In 1842   

Abundance
  
  

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

Abundance In Sun
~-9999 %   
~0.0000001 %   
26

Abundance In Meteorites
Not Available   
0.00 %   
36

Abundance In Earth's Crust
Not Available   
0.00 %   
32

Abundance In Oceans
Not Available   
0.00 %   
36

Uses

Uses & Benefits
  • Francium has no known uses as it has a half life of only 22 minutes.
  
  • It has a tendency to get tarnished in the open air, but when alloyed with elements like erbium, vanadium, its hardness levels decreases.
  • Its compounds like Erbium oxide is used in safety glasses of welders and metal workers.
  

Industrial Uses
NA   
Chemical Industry   

Medical Uses
NA   
NA   

Other Uses
NA   
Alloys   

Biological Properties
  
  

Toxicity
NA   
Mildly 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+
1,522.00 °C   
28

Boiling Point
677.00 °C   
99+
2,510.00 °C   
99+

Appearance
  
  

Physical State
Solid   
Solid   

Color
NA   
Silvery White   

Luster
NA   
Lustrous   

Hardness
  
  

Brinell Hardness
Not Available   
814.00 MPa   
11

Vickers Hardness
Not Available   
589.00 MPa   
19

Speed of Sound
Not Available   
2,830.00 m/s   
28

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   
Er   

Isotopes
  
  

Known Isotopes
33   
6
31   
8

Electronegativity
  
  

Pauling Electronegativity
0.70   
99+
1.24   
36

Allred Rochow Electronegativity
0.86   
99+
1.11   
29

Mulliken-Jaffe Electronegativity
0.68   
25
Not Available   

Allen Electronegativity
0.67   
99+
Not Available   

Electropositivity
  
  

Pauling Electropositivity
3.30   
1
2.76   
18

Ionization Energies
  
  

1st Energy Level
380.00 kJ/mol   
99+
589.30 kJ/mol   
99+

2nd Energy Level
Not Available   
1,150.00 kJ/mol   
99+

3rd Energy Level
Not Available   
2,194.00 kJ/mol   
99+

4th Energy Level
Not Available   
4,120.00 kJ/mol   
33

Electrochemical Equivalent
8.32 g/amp-hr   
1
2.08 g/amp-hr   
28

Electron Work Function
Not Available   
Not Available   

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

Atomic Properties

Atomic Number
87   
31
68   
99+

Electron Configuration
[Rn] 7s1   
[Xe] 4f12 6s2   

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

Crystal Lattice
BCC-Crystal-Structure-.jpg#100   
HCP-Crystal-Structure-of-Erbium.jpg#100   

Atom
  
  

Number of Protons
87   
31
68   
99+

Number of Neutrons
136   
17
99   
33

Number of Electrons
87   
31
68   
99+

Radius of an Atom
  
  

Atomic Radius
Not Available   
176.00 pm   
18

Covalent Radius
260.00 pm   
1
189.00 pm   
19

Van der Waals Radius
348.00 pm   
1
Not Available   

Atomic Weight
223.00 amu   
27
167.26 amu   
99+

Atomic Volume
Not Available   
18.40 cm3/mol   
25

Adjacent Atomic Numbers
  
  

Previous Element
Polonium
  
Holmium
  

Next Element
Radium
  
Thulium
  

Valence Electron Potential
8.00 (-eV)   
99+
49.00 (-eV)   
29

Lattice Constant
Not Available   
355.88 pm   
39

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

Lattice C/A Ratio
Not Available   
1.57   
17

Mechanical Properties

Density
  
  

Density At Room Temperature
1.87 g/cm3   
99+
9.07 g/cm3   
99+

Density When Liquid (at m.p.)
Not Available   
8.86 g/cm3   
23

Tensile Strength
Not Available   
Not Available   

Viscosity
Not Available   
Not Available   

Vapor Pressure
  
  

Vapor Pressure at 1000 K
Not Available   
0.00 (Pa)   
20

Elasticity properties
  
  

Shear Modulus
Not Available   
28.30 GPa   
25

Bulk Modulus
Not Available   
44.40 GPa   
27

Young's Modulus
Not Available   
69.90 GPa   
29

Poisson Ratio
Not Available   
0.24   
28

Other Mechanical Properties
NA   
Malleable   

Magnetic Properties

Magnetic Characteristics
  
  

Specific Gravity
Not Available   
9.07   
32

Magnetic Ordering
Paramagnetic   
Paramagnetic   

Electrical Properties
  
  

Electrical Property
Poor Conductor   
Conductor   

Resistivity
3.00 nΩ·m   
99+
0.86 nΩ·m   
99+

Electrical Conductivity
0.03 106/cm Ω   
40
0.01 106/cm Ω   
99+

Electron Affinity
Not Available   
50.00 kJ/mol   
21

Thermal Properties

Specific Heat
Not Available   
0.17 J/(kg K)   
34

Molar Heat Capacity
Not Available   
28.12 J/mol·K   
11

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

Critical Temperature
Not Available   
Not Available   

Thermal Expansion
Not Available   
12.20 µm/(m·K)   
31

Enthalpy
  
  

Enthalpy of Vaporization
Not Available   
261.00 kJ/mol   
35

Enthalpy of Fusion
Not Available   
17.20 kJ/mol   
15

Enthalpy of Atomization
71.00 kJ/mol   
99+
314.00 kJ/mol   
33

Standard Molar Entropy
Not Available   
73.10 J/mol.K   
11

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