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Erbium vs Francium


Francium vs Erbium


Periodic Table

Symbol
Er   
Fr   

Group Number
Not Available   
1   
17

Period Number
6   
7   

Block
f block   
s block   

Element Family
Lanthanide   
Alkali   

CAS Number
7440520   
35
7440735   
18

Space Group Name
P63/mmc   
Not Available   

Space Group Number
194.00   
5
Not Available   

Facts

Interesting Facts
  • Erbium metal is used as alloyed with Vanadium to make it softer.
  • Recent studies shows that it is helpful for metabolism.
  
  • 223 Francium has the longest half life at 21.8.
  • Francium metal is produced by alpha decay in 227Actinium 227.
  

Sources
Mining   
Formed by Decay Process, Mining   

History
  
  

Who Discovered
Carl Gustaf Mosander   
Marguerite Perey   

Discovery
In 1842   
In 1939   

Abundance
  
  

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

Abundance In Sun
~0.0000001 %   
26
~-9999 %   

Abundance In Meteorites
0.00 %   
36
Not Available   

Abundance In Earth's Crust
0.00 %   
32
Not Available   

Abundance In Oceans
0.00 %   
36
Not Available   

Uses

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

Industrial Uses
Chemical Industry   
NA   

Medical Uses
NA   
NA   

Other Uses
Alloys   
NA   

Biological Properties
  
  

Toxicity
Mildly Toxic   
NA   

Present in Human Body
No   
No   

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

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

Physical Properties

Melting Point
1,522.00 °C   
28
27.00 °C   
99+

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

Appearance
  
  

Physical State
Solid   
Solid   

Color
Silvery White   
NA   

Luster
Lustrous   
NA   

Hardness
  
  

Brinell Hardness
814.00 MPa   
11
Not Available   

Vickers Hardness
589.00 MPa   
19
Not Available   

Speed of Sound
2,830.00 m/s   
28
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
Er   
Fr   

Isotopes
  
  

Known Isotopes
31   
8
33   
6

Electronegativity
  
  

Pauling Electronegativity
1.24   
36
0.70   
99+

Allred Rochow Electronegativity
1.11   
29
0.86   
99+

Mulliken-Jaffe Electronegativity
Not Available   
0.68   
25

Allen Electronegativity
Not Available   
0.67   
99+

Electropositivity
  
  

Pauling Electropositivity
2.76   
18
3.30   
1

Ionization Energies
  
  

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

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

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

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

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

Electron Work Function
Not Available   
Not Available   

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

Atomic Properties

Atomic Number
68   
99+
87   
31

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

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

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

Atom
  
  

Number of Protons
68   
99+
87   
31

Number of Neutrons
99   
33
136   
17

Number of Electrons
68   
99+
87   
31

Radius of an Atom
  
  

Atomic Radius
176.00 pm   
18
Not Available   

Covalent Radius
189.00 pm   
19
260.00 pm   
1

Van der Waals Radius
Not Available   
348.00 pm   
1

Atomic Weight
167.26 amu   
99+
223.00 amu   
27

Atomic Volume
18.40 cm3/mol   
25
Not Available   

Adjacent Atomic Numbers
  
  

Previous Element
Holmium
  
Polonium
  

Next Element
Thulium
  
Radium
  

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

Lattice Constant
355.88 pm   
39
Not Available   

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

Lattice C/A Ratio
1.57   
17
Not Available   

Mechanical Properties

Density
  
  

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

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

Tensile Strength
Not Available   
Not Available   

Viscosity
Not Available   
Not Available   

Vapor Pressure
  
  

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

Elasticity properties
  
  

Shear Modulus
28.30 GPa   
25
Not Available   

Bulk Modulus
44.40 GPa   
27
Not Available   

Young's Modulus
69.90 GPa   
29
Not Available   

Poisson Ratio
0.24   
28
Not Available   

Other Mechanical Properties
Malleable   
NA   

Magnetic Properties

Magnetic Characteristics
  
  

Specific Gravity
9.07   
32
Not Available   

Magnetic Ordering
Paramagnetic   
Paramagnetic   

Electrical Properties
  
  

Electrical Property
Conductor   
Poor Conductor   

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

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

Electron Affinity
50.00 kJ/mol   
21
Not Available   

Thermal Properties

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

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

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

Critical Temperature
Not Available   
Not Available   

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

Enthalpy
  
  

Enthalpy of Vaporization
261.00 kJ/mol   
35
Not Available   

Enthalpy of Fusion
17.20 kJ/mol   
15
Not Available   

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

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

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