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Rhodium vs Neptunium


Neptunium vs Rhodium


Periodic Table

Symbol
Rh  
Np  

Group Number
9  
9
3  
15

Period Number
5  
7  

Block
d block  
f block  

Element Family
Transition Metal  
Actinide  

CAS Number
7440166  
99+
7439998  
99+

Space Group Name
Fm_ 3m  
Pnma  

Space Group Number
225.00  
3
62.00  
14

Facts

Interesting Facts
  • 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.
  
Neptunium was the first transuranium element to be discovered.  

Sources
Earth's crust, Found As a By-product, Found in Minerals, Mining  
Made by Bombarding Uranium with Neutrons, Ores of metals  

History
  
  

Who Discovered
William Hyde Wollaston  
Edwin McMillan and Philip H. Abelson  

Discovery
In 1804  
In 1940  

Abundance
  
  

Abundance In Universe
0.00 %  
27
0.00 %  
40

Abundance In Sun
0.00 %  
25
0.00 %  
26

Abundance In Meteorites
0.00 %  
36
0.00 %  
99+

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

Abundance In Oceans
-  
-  

Abundance In Humans
0.00 %  
24
0.00 %  
24

Uses

Uses & Benefits
  • 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.
  
  • Currently known uses of Neptunium metal are limited to research purpose only.
  • Neptunium’s isotope neptunium-237 is used as a neutron detectors.
  

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

Medical Uses
-  
-  

Other Uses
Alloys  
Alloys, Nuclear Research, Research Purposes  

Biological Properties
  
  

Toxicity
-  
Toxic  

Present in Human Body
No  
No  

In Blood
0.00 Blood/mg dm-3  
37
0.00 Blood/mg dm-3  
40

In Bone
0.00 p.p.m.  
99+
0.00 p.p.m.  
99+

Physical

Melting Point
1,966.00 °C  
12
640.00 °C  
99+

Boiling Point
3,727.00 °C  
17
3,902.00 °C  
13

Appearance
  
  

Physical State
Solid  
Solid  

Color
Silvery White  
Silver  

Luster
Metallic  
Metallic  

Hardness
  
  

Mohs Hardness
6.00  
6
6.00  
6

Brinell Hardness
980.00 MPa  
10
622.00 MPa  
23

Vickers Hardness
1,100.00 MPa  
15
640.00 MPa  
23

Speed of Sound
4,700.00 m/s  
19
2,260.00 m/s  
99+

Optical Properties
  
  

Refractive Index
2.40  
7
1.30  
99+

Reflectivity
84.00 %  
5
64.00 %  
19

Allotropes
No  
No  

α Allotropes
-  
-  

β Allotropes
-  
-  

γ Allotropes
-  
-  

Chemical

Chemical Formula
Rh  
Np  

Isotopes
  
  

Known Isotopes
16  
23
20  
19

Electronegativity
  
  

Pauling Electronegativity
2.28  
4
1.36  
30

Sanderson Electronegativity
2.28  
5
1.36  
23

Allred Rochow Electronegativity
1.45  
17
1.22  
27

Mulliken-Jaffe Electronegativity
2.28  
4
1.36  
31

Allen Electronegativity
1.56  
27
1.36  
37

Electropositivity
  
  

Pauling Electropositivity
1.72  
99+
2.64  
25

Ionization Energies
  
  

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

2nd Energy Level
1,740.00 kJ/mol  
27
1,128.00 kJ/mol  
99+

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

4th Energy Level
7,197.00 kJ/mol  
11
3,242.00 kJ/mol  
99+

5th Energy Level
7,197.00 kJ/mol  
26
6,180.00 kJ/mol  
99+

6th Energy Level
7,197.00 kJ/mol  
40
5,785.00 kJ/mol  
99+

7th Energy level
7,197.00 kJ/mol  
35
6,040.00 kJ/mol  
99+

8th Energy Level
3,480.00 kJ/mol  
99+
6,040.00 kJ/mol  
99+

9th Energy Level
5,090.00 kJ/mol  
99+
6,180.00 kJ/mol  
99+

10th Energy Level
7,197.00 kJ/mol  
33
6,180.00 kJ/mol  
99+

11th Energy Level
7,197.00 kJ/mol  
32
6,180.00 kJ/mol  
99+

12th Energy Level
7,190.00 kJ/mol  
99+
61,800.00 kJ/mol  
13

13th Energy Level
7,190.00 kJ/mol  
27
6,180.00 kJ/mol  
40

14th Energy Level
7,197.00 kJ/mol  
21
6,180.00 kJ/mol  
29

15th Energy Level
71,900.00 kJ/mol  
23
60,600.00 kJ/mol  
99+

16th Energy Level
71,900.00 kJ/mol  
18
60,420.00 kJ/mol  
31

17th Energy Level
719.70 kJ/mol  
39
604.00 kJ/mol  
99+

18th Energy Level
7,197.00 kJ/mol  
29
6,040.00 kJ/mol  
99+

19th Energy Level
719.70 kJ/mol  
36
604.50 kJ/mol  
99+

20th Energy Level
719.00 kJ/mol  
30
604.00 kJ/mol  
99+

21st Energy Level
719.70 kJ/mol  
99+
6,040.00 kJ/mol  
17

22nd Energy Level
719.00 kJ/mol  
24
604.00 kJ/mol  
40

23rd Energy Level
719.70 kJ/mol  
99+
6,040.00 kJ/mol  
18

24th Energy Level
719.70 kJ/mol  
23
604.50 kJ/mol  
99+

25th Energy Level
719.00 kJ/mol  
23
604.00 kJ/mol  
99+

26th Energy Level
719.70 kJ/mol  
23
604.00 kJ/mol  
99+

27th Energy Level
719.70 kJ/mol  
22
604.00 kJ/mol  
99+

28th Energy Level
719.70 kJ/mol  
28
604.00 kJ/mol  
99+

29th Energy Level
719.70 kJ/mol  
29
604.00 kJ/mol  
99+

30th Energy Level
719.00 kJ/mol  
23
604.00 kJ/mol  
99+

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

Electron Work Function
4.98 eV  
10
4.90 eV  
12

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

Atomic

Atomic Number
45  
99+
93  
25

Electron Configuration
[Kr] 4d8 5s1  
[Rn] 5f4 6d1 7s2  

Crystal Structure
Face Centered Cubic (FCC)  
Orthorhombic (ORTH)  

Crystal Lattice
FCC-Crystal-Structure-of-Rhodium.jpg#100  
ORTH-Crystal-Structure-of-Neptunium.jpg#100  

Atom
  
  

Number of Protons
45  
99+
93  
25

Number of Neutrons
58  
99+
144  
15

Number of Electrons
45  
99+
93  
25

Radius of an Atom
  
  

Atomic Radius
134.00 pm  
99+
155.00 pm  
32

Covalent Radius
142.00 pm  
99+
190.00 pm  
18

Van der Waals Radius
200.00 pm  
35
221.00 pm  
27

Atomic Weight
102.91 amu  
99+
237.00 amu  
22

Atomic Volume
8.30 cm3/mol  
99+
11.62 cm3/mol  
99+

Adjacent Atomic Numbers
  
  

Previous Element
Ruthenium
  
Uranium
  

Next Element
Palladium
  
Plutonium
  

Valence Electron Potential
64.00 (-eV)  
22
96.00 (-eV)  
9

Lattice Constant
380.34 pm  
30
666.30 pm  
3

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

Lattice C/A Ratio
1.73  
7
1.43  
99+

Mechanical

Density
  
  

Density At Room Temperature
12.41 g/cm3  
30
19.38 g/cm3  
14

Density When Liquid (at m.p.)
10.70 g/cm3  
35
20.25 g/cm3  
10

Tensile Strength
951.00 MPa  
5
125.00 MPa  
26

Viscosity
0.00  
25
0.00  
25

Vapor Pressure
  
  

Vapor Pressure at 1000 K
0.00 (Pa)  
37
0.00 (Pa)  
22

Vapor Pressure at 2000 K
0.02 (Pa)  
19
0.11 (Pa)  
17

Elasticity properties
  
  

Shear Modulus
150.00 GPa  
6
5.60 GPa  
99+

Bulk Modulus
275.00 GPa  
5
180.00 GPa  
9

Young's Modulus
380.00 GPa  
5
46.00 GPa  
99+

Poisson Ratio
0.26  
22
0.26  
22

Other Mechanical Properties
Malleable  
Ductile  

Magnetic

Magnetic Characteristics
  
  

Specific Gravity
12.41  
32
20.25  
15

Magnetic Ordering
Paramagnetic  
Paramagnetic  

Permeability
0.00 H/m  
17
0.00 H/m  
6

Susceptibility
0.00  
24
0.00  
24

Electrical Properties
  
  

Electrical Property
Conductor  
Conductor  

Resistivity
43.30 nΩ·m  
99+
1.22 nΩ·m  
99+

Electrical Conductivity
0.21 106/cm Ω  
8
0.01 106/cm Ω  
99+

Electron Affinity
109.70 kJ/mol  
8
118.60 kJ/mol  
6

Thermal

Specific Heat
0.24 J/(kg K)  
22
0.12 J/(kg K)  
99+

Molar Heat Capacity
24.98 J/mol·K  
99+
29.46 J/mol·K  
10

Thermal Conductivity
150.00 W/m·K  
9
6.30 W/m·K  
99+

Critical Temperature
2,237.00 K  
13
913.00 K  
99+

Thermal Expansion
8.20 µm/(m·K)  
99+
13.30 µm/(m·K)  
35

Enthalpy
  
  

Enthalpy of Vaporization
495.40 kJ/mol  
16
336.00 kJ/mol  
39

Enthalpy of Fusion
21.76 kJ/mol  
10
3.20 kJ/mol  
99+

Enthalpy of Atomization
556.50 kJ/mol  
16
275.30 kJ/mol  
99+

Standard Molar Entropy
31.50 J/mol.K  
99+
64.00 J/mol.K  
21

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