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Curium vs Neptunium


Neptunium vs Curium


Periodic Table

Symbol
Cm  
Np  

Group Number
3  
15
3  
15

Period Number
7  
7  

Block
f block  
f block  

Element Family
Actinide  
Actinide  

CAS Number
7440519  
36
7439998  
99+

Space Group Name
-  
Pnma  

Space Group Number
225.00  
3
62.00  
14

Facts

Interesting Facts
  • Curium metal does not occur free in nature.
  • Curium metal is a synthetically produced metal.
  
Neptunium was the first transuranium element to be discovered.  

Sources
Bombarding Plutonium with Helium Ions  
Made by Bombarding Uranium with Neutrons, Ores of metals  

History
  
  

Who Discovered
Glenn T. Seaborg, Ralph A. James, Albert Ghiorso  
Edwin McMillan and Philip H. Abelson  

Discovery
In 1944  
In 1940  

Abundance
  
  

Abundance In Universe
0.00 %  
35
0.00 %  
40

Abundance In Sun
0.00 %  
30
0.00 %  
26

Abundance In Meteorites
0.00 %  
99+
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
  • Curium metal is used to provide power to electrical equipment for space missions.
  
  • 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
-  
-  

Medical Uses
-  
-  

Other Uses
Research Purposes  
Alloys, Nuclear Research, Research Purposes  

Biological Properties
  
  

Toxicity
-  
Toxic  

Present in Human Body
No  
No  

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

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

Physical

Melting Point
1,340.00 °C  
34
640.00 °C  
99+

Boiling Point
3,110.00 °C  
31
3,902.00 °C  
13

Appearance
  
  

Physical State
Solid  
Solid  

Color
Silver  
Silver  

Luster
Metallic  
Metallic  

Hardness
  
  

Mohs Hardness
2.00  
17
6.00  
6

Brinell Hardness
320.00 MPa  
40
622.00 MPa  
23

Vickers Hardness
461.00 MPa  
37
640.00 MPa  
23

Speed of Sound
2,260.00 m/s  
99+
2,260.00 m/s  
99+

Optical Properties
  
  

Refractive Index
1.30  
99+
1.30  
99+

Reflectivity
60.00 %  
23
64.00 %  
19

Allotropes
No  
No  

α Allotropes
-  
-  

β Allotropes
-  
-  

γ Allotropes
-  
-  

Chemical

Chemical Formula
Cm  
Np  

Isotopes
  
  

Known Isotopes
15  
24
20  
19

Electronegativity
  
  

Pauling Electronegativity
1.30  
33
1.36  
30

Sanderson Electronegativity
1.30  
25
1.36  
23

Allred Rochow Electronegativity
1.20  
28
1.22  
27

Mulliken-Jaffe Electronegativity
1.30  
33
1.36  
31

Allen Electronegativity
1.30  
40
1.36  
37

Electropositivity
  
  

Pauling Electropositivity
2.70  
22
2.64  
25

Ionization Energies
  
  

1st Energy Level
581.00 kJ/mol  
99+
604.50 kJ/mol  
99+

2nd Energy Level
1,196.00 kJ/mol  
99+
1,128.00 kJ/mol  
99+

3rd Energy Level
2,026.00 kJ/mol  
99+
1,997.00 kJ/mol  
99+

4th Energy Level
3,550.00 kJ/mol  
99+
3,242.00 kJ/mol  
99+

5th Energy Level
5,810.00 kJ/mol  
99+
6,180.00 kJ/mol  
99+

6th Energy Level
5,810.00 kJ/mol  
99+
5,785.00 kJ/mol  
99+

7th Energy level
5,810.00 kJ/mol  
99+
6,040.00 kJ/mol  
99+

8th Energy Level
5,810.00 kJ/mol  
99+
6,040.00 kJ/mol  
99+

9th Energy Level
6,690.00 kJ/mol  
37
6,180.00 kJ/mol  
99+

10th Energy Level
5,810.00 kJ/mol  
99+
6,180.00 kJ/mol  
99+

11th Energy Level
5,810.00 kJ/mol  
99+
6,180.00 kJ/mol  
99+

12th Energy Level
58,100.00 kJ/mol  
19
61,800.00 kJ/mol  
13

13th Energy Level
5,810.00 kJ/mol  
99+
6,180.00 kJ/mol  
40

14th Energy Level
5,810.00 kJ/mol  
40
6,180.00 kJ/mol  
29

15th Energy Level
58,100.00 kJ/mol  
99+
60,600.00 kJ/mol  
99+

16th Energy Level
58,100.00 kJ/mol  
99+
60,420.00 kJ/mol  
31

17th Energy Level
581.00 kJ/mol  
99+
604.00 kJ/mol  
99+

18th Energy Level
5,810.00 kJ/mol  
99+
6,040.00 kJ/mol  
99+

19th Energy Level
581.00 kJ/mol  
99+
604.50 kJ/mol  
99+

20th Energy Level
581.00 kJ/mol  
99+
604.00 kJ/mol  
99+

21st Energy Level
5,810.00 kJ/mol  
20
6,040.00 kJ/mol  
17

22nd Energy Level
581.00 kJ/mol  
99+
604.00 kJ/mol  
40

23rd Energy Level
5,810.00 kJ/mol  
20
6,040.00 kJ/mol  
18

24th Energy Level
581.00 kJ/mol  
99+
604.50 kJ/mol  
99+

25th Energy Level
581.00 kJ/mol  
99+
604.00 kJ/mol  
99+

26th Energy Level
581.00 kJ/mol  
99+
604.00 kJ/mol  
99+

27th Energy Level
581.00 kJ/mol  
99+
604.00 kJ/mol  
99+

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

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

30th Energy Level
581.00 kJ/mol  
99+
604.00 kJ/mol  
99+

Electrochemical Equivalent
3.07 g/amp-hr  
19
1.77 g/amp-hr  
99+

Electron Work Function
4.50 eV  
19
4.90 eV  
12

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

Atomic

Atomic Number
96  
22
93  
25

Electron Configuration
[Rn] 5f7 6d1 7s2  
[Rn] 5f4 6d1 7s2  

Crystal Structure
Double Hexagonal Close Packed (DHCP)  
Orthorhombic (ORTH)  

Crystal Lattice
DHCP-Crystal-Structure-of-Curium.jpg#100  
ORTH-Crystal-Structure-of-Neptunium.jpg#100  

Atom
  
  

Number of Protons
96  
22
93  
25

Number of Neutrons
151  
11
144  
15

Number of Electrons
96  
22
93  
25

Radius of an Atom
  
  

Atomic Radius
174.00 pm  
22
155.00 pm  
32

Covalent Radius
169.00 pm  
28
190.00 pm  
18

Van der Waals Radius
200.00 pm  
35
221.00 pm  
27

Atomic Weight
247.00 amu  
18
237.00 amu  
22

Atomic Volume
18.28 cm3/mol  
38
11.62 cm3/mol  
99+

Adjacent Atomic Numbers
  
  

Previous Element
Americium
  
Uranium
  

Next Element
Berkelium
  
Plutonium
  

Valence Electron Potential
44.50 (-eV)  
39
96.00 (-eV)  
9

Lattice Constant
336.25 pm  
99+
666.30 pm  
3

Lattice Angles
-  
π/2, π/2, π/2  

Lattice C/A Ratio
1.67  
11
1.43  
99+

Mechanical

Density
  
  

Density At Room Temperature
13.51 g/cm3  
26
19.38 g/cm3  
14

Density When Liquid (at m.p.)
13.85 g/cm3  
25
20.25 g/cm3  
10

Tensile Strength
350.00 MPa  
12
125.00 MPa  
26

Viscosity
0.00  
25
0.00  
25

Vapor Pressure
  
  

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

Vapor Pressure at 2000 K
0.00 (Pa)  
24
0.11 (Pa)  
17

Elasticity properties
  
  

Shear Modulus
32.00 GPa  
24
5.60 GPa  
99+

Bulk Modulus
40.00 GPa  
38
180.00 GPa  
9

Young's Modulus
0.00 GPa  
99+
46.00 GPa  
99+

Poisson Ratio
0.35  
9
0.26  
22

Other Mechanical Properties
-  
Ductile  

Magnetic

Magnetic Characteristics
  
  

Specific Gravity
13.51  
28
20.25  
15

Magnetic Ordering
Antiferromagnetic  
Paramagnetic  

Permeability
0.00 H/m  
17
0.00 H/m  
6

Susceptibility
0.00  
24
0.00  
24

Electrical Properties
  
  

Electrical Property
-  
Conductor  

Resistivity
1.25 nΩ·m  
99+
1.22 nΩ·m  
99+

Electrical Conductivity
0.13 106/cm Ω  
19
0.01 106/cm Ω  
99+

Electron Affinity
0.00 kJ/mol  
99+
118.60 kJ/mol  
6

Thermal

Specific Heat
0.10 J/(kg K)  
99+
0.12 J/(kg K)  
99+

Molar Heat Capacity
27.50 J/mol·K  
21
29.46 J/mol·K  
10

Thermal Conductivity
11.00 W/m·K  
99+
6.30 W/m·K  
99+

Critical Temperature
1,340.00 K  
99+
913.00 K  
99+

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

Enthalpy
  
  

Enthalpy of Vaporization
331.60 kJ/mol  
40
336.00 kJ/mol  
39

Enthalpy of Fusion
15.00 kJ/mol  
22
3.20 kJ/mol  
99+

Enthalpy of Atomization
-  
275.30 kJ/mol  
99+

Standard Molar Entropy
52.50 J/mol.K  
36
64.00 J/mol.K  
21

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