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Protactinium vs Erbium


Erbium vs Protactinium


Periodic Table

Symbol
Pa   
Er   

Group Number
Not Available   
Not Available   

Period Number
7   
6   

Block
f block   
f block   

Element Family
Actinide   
Lanthanide   

CAS Number
7440133   
99+
7440520   
35

Space Group Name
I4/mmm   
P63/mmc   

Space Group Number
139.00   
8
194.00   
5

Facts

Interesting Facts
  • Protactinium metal has 29 isotopes.
  • Isotopes of Protactinium-231 used in nuclear weapon.
  
  • Erbium metal is used as alloyed with Vanadium to make it softer.
  • Recent studies shows that it is helpful for metabolism.
  

Sources
Found in Uranium Ores, Mining, Ores of metals   
Mining   

History
  
  

Who Discovered
William Crookes   
Carl Gustaf Mosander   

Discovery
In 1900   
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
0.00 %   
99+
0.00 %   
32

Abundance In Oceans
0.00 %   
99+
0.00 %   
36

Uses

Uses & Benefits
  • Currently known uses of Protactinium metal are limited to research purpose only.
  
  • 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
Highly Toxic   
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
1,568.00 °C   
21
1,522.00 °C   
28

Boiling Point
4,027.00 °C   
12
2,510.00 °C   
99+

Appearance
  
  

Physical State
Solid   
Solid   

Color
Silver   
Silvery White   

Luster
Metallic   
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
Pa   
Er   

Isotopes
  
  

Known Isotopes
27   
12
31   
8

Electronegativity
  
  

Pauling Electronegativity
1.50   
27
1.24   
36

Allred Rochow Electronegativity
1.14   
28
1.11   
29

Electropositivity
  
  

Pauling Electropositivity
2.50   
27
2.76   
18

Ionization Energies
  
  

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

2nd Energy Level
1,128.00 kJ/mol   
99+
1,150.00 kJ/mol   
99+

3rd Energy Level
1,814.00 kJ/mol   
99+
2,194.00 kJ/mol   
99+

4th Energy Level
2,991.00 kJ/mol   
99+
4,120.00 kJ/mol   
33

Electrochemical Equivalent
1.72 g/amp-hr   
99+
2.08 g/amp-hr   
28

Electron Work Function
Not Available   
Not Available   

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

Atomic Properties

Atomic Number
91   
27
68   
99+

Electron Configuration
[Rn] 5f2 6d1 7s2   
[Xe] 4f12 6s2   

Crystal Structure
Tetragonal (TETR)   
Hexagonal Close Packed (HCP)   

Crystal Lattice
TETR-Crystal-Structure-of-Protactinium.jpg#100   
HCP-Crystal-Structure-of-Erbium.jpg#100   

Atom
  
  

Number of Protons
91   
27
68   
99+

Number of Neutrons
122   
21
99   
33

Number of Electrons
91   
27
68   
99+

Radius of an Atom
  
  

Atomic Radius
163.00 pm   
25
176.00 pm   
18

Covalent Radius
200.00 pm   
11
189.00 pm   
19

Van der Waals Radius
243.00 pm   
11
Not Available   

Atomic Weight
231.04 amu   
24
167.26 amu   
99+

Atomic Volume
15.00 cm3/mol   
34
18.40 cm3/mol   
25

Adjacent Atomic Numbers
  
  

Previous Element
Thorium
  
Holmium
  

Next Element
Uranium
  
Thulium
  

Valence Electron Potential
92.00 (-eV)   
11
49.00 (-eV)   
29

Lattice Constant
392.50 pm   
23
355.88 pm   
39

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

Lattice C/A Ratio
Not Available   
1.57   
17

Mechanical Properties

Density
  
  

Density At Room Temperature
15.37 g/cm3   
20
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
Unknown   
Malleable   

Magnetic Properties

Magnetic Characteristics
  
  

Specific Gravity
15.37   
12
9.07   
32

Magnetic Ordering
Paramagnetic   
Paramagnetic   

Electrical Properties
  
  

Electrical Property
Conductor   
Conductor   

Resistivity
177.00 nΩ·m   
21
0.86 nΩ·m   
99+

Electrical Conductivity
0.05 106/cm Ω   
34
0.01 106/cm Ω   
99+

Electron Affinity
Not Available   
50.00 kJ/mol   
21

Thermal Properties

Specific Heat
0.12 J/(kg K)   
40
0.17 J/(kg K)   
34

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

Thermal Conductivity
47.00 W/m·K   
32
14.50 W/m·K   
99+

Critical Temperature
Not Available   
Not Available   

Thermal Expansion
9.90 µm/(m·K)   
40
12.20 µm/(m·K)   
31

Enthalpy
  
  

Enthalpy of Vaporization
Not Available   
261.00 kJ/mol   
35

Enthalpy of Fusion
12.34 kJ/mol   
28
17.20 kJ/mol   
15

Enthalpy of Atomization
Not Available   
314.00 kJ/mol   
33

Standard Molar Entropy
198.10 J/mol.K   
1
73.10 J/mol.K   
11

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