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Protactinium vs Fermium


Fermium vs Protactinium


Periodic Table

Symbol
Pa  
Fm  

Group Number
3  
15
3  
15

Period Number
7  
7  

Block
f block  
f block  

Element Family
Actinide  
Actinide  

CAS Number
7440133  
99+
7440724  
19

Space Group Name
I4/mmm  
-  

Space Group Number
139.00  
11
194.00  
7

Facts

Interesting Facts
  • Protactinium metal has 29 isotopes.
  • Isotopes of Protactinium-231 used in nuclear weapon.
  
  • Fermium metal is highly radioactive in nature.
  • Fermium is synthetically produced metal.
  

Sources
Found in Uranium Ores, Mining, Ores of metals  
Bombarding Pu-239 with Neutrons  

History
  
  

Who Discovered
William Crookes  
Lawrence Berkeley National Laboratory  

Discovery
In 1900  
In 1952  

Abundance
  
  

Abundance In Universe
0.00 %  
17
0.00 %  
35

Abundance In Sun
0.00 %  
26
0.00 %  
30

Abundance In Meteorites
-  
0.00 %  
99+

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

Abundance In Oceans
0.00 %  
99+
-  

Abundance In Humans
0.00 %  
24
-  

Uses

Uses & Benefits
  • Currently known uses of Protactinium metal are limited to research purpose only.
  
  • Currently known uses of Fermium metal are limited to research purpose only.
  

Industrial Uses
-  
-  

Medical Uses
-  
-  

Other Uses
-  
-  

Biological Properties
  
  

Toxicity
Highly 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
1,568.00 °C  
21
1,527.00 °C  
26

Boiling Point
4,027.00 °C  
12
0.00 °C  
99+

Appearance
  
  

Physical State
Solid  
Solid  

Color
Silver  
-  

Luster
Metallic  
-  

Hardness
  
  

Mohs Hardness
5.00  
8
6.00  
6

Brinell Hardness
125.00 MPa  
99+
500.00 MPa  
28

Vickers Hardness
220.00 MPa  
99+
600.00 MPa  
28

Speed of Sound
12,400.00 m/s  
3
2,500.00 m/s  
99+

Optical Properties
  
  

Refractive Index
1.60  
33
1.30  
99+

Reflectivity
60.00 %  
23
59.00 %  
24

Allotropes
No  
No  

α Allotropes
-  
-  

β Allotropes
-  
-  

γ Allotropes
-  
-  

Chemical

Chemical Formula
Pa  
Fm  

Isotopes
  
  

Known Isotopes
27  
12
18  
21

Electronegativity
  
  

Pauling Electronegativity
1.50  
28
1.30  
33

Sanderson Electronegativity
1.50  
18
1.30  
25

Allred Rochow Electronegativity
1.14  
29
1.20  
28

Mulliken-Jaffe Electronegativity
1.50  
26
1.30  
33

Allen Electronegativity
1.50  
32
1.30  
40

Electropositivity
  
  

Pauling Electropositivity
2.50  
27
2.70  
22

Ionization Energies
  
  

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

2nd Energy Level
1,128.00 kJ/mol  
99+
1,225.00 kJ/mol  
99+

3rd Energy Level
1,814.00 kJ/mol  
99+
2,363.00 kJ/mol  
99+

4th Energy Level
2,991.00 kJ/mol  
99+
3,792.00 kJ/mol  
99+

5th Energy Level
5,120.00 kJ/mol  
99+
6,270.00 kJ/mol  
39

6th Energy Level
5,680.00 kJ/mol  
99+
6,270.00 kJ/mol  
99+

7th Energy level
5,680.00 kJ/mol  
99+
6,270.00 kJ/mol  
99+

8th Energy Level
5,680.00 kJ/mol  
99+
6,270.00 kJ/mol  
99+

9th Energy Level
5,120.00 kJ/mol  
99+
7,040.00 kJ/mol  
33

10th Energy Level
5,120.00 kJ/mol  
99+
6,270.00 kJ/mol  
99+

11th Energy Level
5,680.00 kJ/mol  
99+
6,270.00 kJ/mol  
99+

12th Energy Level
5,680.00 kJ/mol  
99+
62,700.00 kJ/mol  
10

13th Energy Level
5,680.00 kJ/mol  
99+
6,270.00 kJ/mol  
38

14th Energy Level
5,680.00 kJ/mol  
99+
6,270.00 kJ/mol  
27

15th Energy Level
56,800.00 kJ/mol  
99+
62,700.00 kJ/mol  
38

16th Energy Level
56,800.00 kJ/mol  
99+
62,700.00 kJ/mol  
28

17th Energy Level
568.50 kJ/mol  
99+
627.00 kJ/mol  
99+

18th Energy Level
5,680.00 kJ/mol  
99+
6,270.00 kJ/mol  
40

19th Energy Level
568.30 kJ/mol  
99+
994.80 kJ/mol  
21

20th Energy Level
568.00 kJ/mol  
99+
627.00 kJ/mol  
99+

21st Energy Level
568.00 kJ/mol  
99+
627.00 kJ/mol  
99+

22nd Energy Level
568.00 kJ/mol  
99+
345.00 kJ/mol  
99+

23rd Energy Level
568.00 kJ/mol  
99+
6,270.00 kJ/mol  
14

24th Energy Level
568.00 kJ/mol  
99+
627.60 kJ/mol  
38

25th Energy Level
568.00 kJ/mol  
99+
627.00 kJ/mol  
40

26th Energy Level
568.00 kJ/mol  
99+
627.60 kJ/mol  
39

27th Energy Level
568.00 kJ/mol  
99+
627.60 kJ/mol  
99+

28th Energy Level
568.00 kJ/mol  
99+
627.60 kJ/mol  
99+

29th Energy Level
568.00 kJ/mol  
99+
627.60 kJ/mol  
99+

30th Energy Level
568.00 kJ/mol  
99+
627.60 kJ/mol  
99+

Electrochemical Equivalent
1.72 g/amp-hr  
99+
3.20 g/amp-hr  
15

Electron Work Function
5.89 eV  
3
4.47 eV  
21

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

Atomic

Atomic Number
91  
27
100  
18

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

Crystal Structure
Tetragonal (TETR)  
Not Known  

Crystal Lattice
TETR-Crystal-Structure-of-Protactinium.jpg#100  
Unknown-Crystal-Structure-of-Fermium.jpg#100  

Atom
  
  

Number of Protons
91  
27
100  
18

Number of Neutrons
122  
22
157  
8

Number of Electrons
91  
27
100  
18

Radius of an Atom
  
  

Atomic Radius
163.00 pm  
27
180.00 pm  
16

Covalent Radius
200.00 pm  
11
180.00 pm  
23

Van der Waals Radius
243.00 pm  
15
245.00 pm  
13

Atomic Weight
231.04 amu  
24
257.00 amu  
15

Atomic Volume
15.00 cm3/mol  
99+
18.00 cm3/mol  
99+

Adjacent Atomic Numbers
  
  

Previous Element
Thorium
  

Next Element
Uranium
  

Valence Electron Potential
92.00 (-eV)  
11
0.00 (-eV)  
99+

Lattice Constant
392.50 pm  
26
350.00 pm  
99+

Lattice Angles
π/2, π/2, π/2  
-  

Lattice C/A Ratio
1.58  
36
1.63  
13

Mechanical

Density
  
  

Density At Room Temperature
15.37 g/cm3  
20
9.70 g/cm3  
99+

Density When Liquid (at m.p.)
15.37 g/cm3  
21
9.70 g/cm3  
99+

Tensile Strength
80.00 MPa  
29
0.10 MPa  
99+

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
0.00 (Pa)  
32
0.00 (Pa)  
30

Elasticity properties
  
  

Shear Modulus
16.00 GPa  
99+
30.00 GPa  
27

Bulk Modulus
47.00 GPa  
26
50.00 GPa  
24

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

Poisson Ratio
0.23  
30
0.35  
9

Other Mechanical Properties
-  
-  

Magnetic

Magnetic Characteristics
  
  

Specific Gravity
15.37  
23
9.70  
99+

Magnetic Ordering
Paramagnetic  
-  

Permeability
0.00 H/m  
10
0.00 H/m  
16

Susceptibility
0.00  
21
0.00  
24

Electrical Properties
  
  

Electrical Property
Conductor  
-  

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

Electrical Conductivity
0.05 106/cm Ω  
39
0.00 106/cm Ω  
99+

Electron Affinity
53.03 kJ/mol  
22
0.00 kJ/mol  
99+

Thermal

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

Molar Heat Capacity
27.20 J/mol·K  
24
27.00 J/mol·K  
29

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

Critical Temperature
1,841.00 K  
25
1,323.00 K  
99+

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

Enthalpy
  
  

Enthalpy of Vaporization
481.00 kJ/mol  
17
319.20 kJ/mol  
99+

Enthalpy of Fusion
12.34 kJ/mol  
34
13.30 kJ/mol  
30

Enthalpy of Atomization
481.90 kJ/mol  
19
-  

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

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