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Protactinium vs Rhodium


Rhodium vs Protactinium


Periodic Table

Symbol
Pa   
Rh   

Group Number
Not Available   
9   
9

Period Number
7   
5   

Block
f block   
d block   

Element Family
Actinide   
Transition Metal   

CAS Number
7440133   
99+
7440166   
99+

Space Group Name
I4/mmm   
Fm_ 3m   

Space Group Number
139.00   
8
225.00   
2

Facts

Interesting Facts
  • Protactinium metal has 29 isotopes.
  • Isotopes of Protactinium-231 used in nuclear weapon.
  
  • Rhodium is the rarest element out of all non-radioactive metals on the earth .
  • Rhodium is one of the most durable and hard metal, which also have high reflectance.
  

Sources
Found in Uranium Ores, Mining, Ores of metals   
Earth's crust, Found As a By-product, Found in Minerals, Mining   

History
  
  

Who Discovered
William Crookes   
William Hyde Wollaston   

Discovery
In 1900   
In 1804   

Abundance
  
  

Abundance In Universe
Not Available   
6 * 10-8 %   
26

Abundance In Sun
~-9999 %   
~0.0000002 %   
25

Abundance In Meteorites
Not Available   
0.00 %   
36

Abundance In Earth's Crust
0.00 %   
99+
0.00 %   
99+

Abundance In Oceans
0.00 %   
99+
Not Available   

Uses

Uses & Benefits
  • Currently known uses of Protactinium metal are limited to research purpose only.
  
  • Rhodium metal is mainly used in catalytic converters for cars as it reduces nitrogen oxides in exhaust gases.
  • It is used as an industrial catalyst for nitric acid, acetic acid, hydrogenation reaction, etc.
  

Industrial Uses
NA   
Aerospace Industry, Automobile Industry, Electrical Industry, Electronic Industry   

Medical Uses
NA   
NA   

Other Uses
NA   
Alloys   

Biological Properties
  
  

Toxicity
Highly Toxic   
NA   

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
1,966.00 °C   
12

Boiling Point
4,027.00 °C   
12
3,727.00 °C   
17

Appearance
  
  

Physical State
Solid   
Solid   

Color
Silver   
Silvery White   

Luster
Metallic   
Metallic   

Hardness
  
  

Mohs Hardness
Not Available   
6.00   
6

Brinell Hardness
Not Available   
980.00 MPa   
9

Vickers Hardness
Not Available   
1,100.00 MPa   
9

Speed of Sound
Not Available   
4,700.00 m/s   
15

Optical Properties
  
  

Reflectivity
Not Available   
84.00 %   
4

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   
Rh   

Isotopes
  
  

Known Isotopes
27   
12
16   
23

Electronegativity
  
  

Pauling Electronegativity
1.50   
27
2.28   
3

Allred Rochow Electronegativity
1.14   
28
1.45   
16

Allen Electronegativity
Not Available   
1.56   
24

Electropositivity
  
  

Pauling Electropositivity
2.50   
27
1.72   
99+

Ionization Energies
  
  

1st Energy Level
568.00 kJ/mol   
99+
719.70 kJ/mol   
29

2nd Energy Level
1,128.00 kJ/mol   
99+
1,740.00 kJ/mol   
26

3rd Energy Level
1,814.00 kJ/mol   
99+
2,997.00 kJ/mol   
27

4th Energy Level
2,991.00 kJ/mol   
99+
Not Available   

Electrochemical Equivalent
1.72 g/amp-hr   
99+
1.28 g/amp-hr   
99+

Electron Work Function
Not Available   
4.98 eV   
6

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

Atomic Properties

Atomic Number
91   
27
45   
99+

Electron Configuration
[Rn] 5f2 6d1 7s2   
[Kr] 4d8 5s1   

Crystal Structure
Tetragonal (TETR)   
Face Centered Cubic (FCC)   

Crystal Lattice
TETR-Crystal-Structure-of-Protactinium.jpg#100   
FCC-Crystal-Structure-of-Rhodium.jpg#100   

Atom
  
  

Number of Protons
91   
27
45   
99+

Number of Neutrons
122   
21
58   
99+

Number of Electrons
91   
27
45   
99+

Radius of an Atom
  
  

Atomic Radius
163.00 pm   
25
134.00 pm   
99+

Covalent Radius
200.00 pm   
11
142.00 pm   
99+

Van der Waals Radius
243.00 pm   
11
200.00 pm   
28

Atomic Weight
231.04 amu   
24
102.91 amu   
99+

Atomic Volume
15.00 cm3/mol   
34
8.30 cm3/mol   
99+

Adjacent Atomic Numbers
  
  

Previous Element
Thorium
  
Ruthenium
  

Next Element
Uranium
  
Palladium
  

Valence Electron Potential
92.00 (-eV)   
11
64.00 (-eV)   
22

Lattice Constant
392.50 pm   
23
380.34 pm   
27

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

Lattice C/A Ratio
Not Available   
Not Available   

Mechanical Properties

Density
  
  

Density At Room Temperature
15.37 g/cm3   
20
12.41 g/cm3   
28

Density When Liquid (at m.p.)
Not Available   
10.70 g/cm3   
14

Tensile Strength
Not Available   
951.00 MPa   
5

Viscosity
Not Available   
Not Available   

Vapor Pressure
  
  

Vapor Pressure at 2000 K
Not Available   
0.02 (Pa)   
19

Elasticity properties
  
  

Shear Modulus
Not Available   
150.00 GPa   
6

Bulk Modulus
Not Available   
275.00 GPa   
5

Young's Modulus
Not Available   
380.00 GPa   
5

Poisson Ratio
Not Available   
0.26   
22

Other Mechanical Properties
Unknown   
Malleable   

Magnetic Properties

Magnetic Characteristics
  
  

Specific Gravity
15.37   
12
12.41   
20

Magnetic Ordering
Paramagnetic   
Paramagnetic   

Electrical Properties
  
  

Electrical Property
Conductor   
Conductor   

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

Electrical Conductivity
0.05 106/cm Ω   
34
0.21 106/cm Ω   
8

Electron Affinity
Not Available   
109.70 kJ/mol   
7

Thermal Properties

Specific Heat
0.12 J/(kg K)   
40
0.24 J/(kg K)   
22

Molar Heat Capacity
Not Available   
24.98 J/mol·K   
99+

Thermal Conductivity
47.00 W/m·K   
32
150.00 W/m·K   
9

Critical Temperature
Not Available   
Not Available   

Thermal Expansion
9.90 µm/(m·K)   
40
8.20 µm/(m·K)   
99+

Enthalpy
  
  

Enthalpy of Vaporization
Not Available   
495.40 kJ/mol   
12

Enthalpy of Fusion
12.34 kJ/mol   
28
21.76 kJ/mol   
10

Enthalpy of Atomization
Not Available   
556.50 kJ/mol   
12

Standard Molar Entropy
198.10 J/mol.K   
1
31.50 J/mol.K   
99+

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