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Protactinium Polonium Comparison


Polonium Protactinium comparison


Periodic Table

Symbol
Pa  
Po  

Group Number
3  
15
16  
2

Period Number
7  
6  

Block
f block  
p block  

Element Family
Actinide  
Post-​Transition  

CAS Number
7440133  
99+
7440086  
99+

Space Group Name
I4/mmm  
Pm-3m  

Space Group Number
139.00  
11
221.00  
4

Facts

Interesting Facts
  • Protactinium metal has 29 isotopes.
  • Isotopes of Protactinium-231 used in nuclear weapon.
  
  • Polonium was the first radioactive element to be discovered.
  • Polonium element and its compounds are highly radioactive.
  • Its alloy with Beryllium provides source of neutrons.
  

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

History
  
  

Who Discovered
William Crookes  
Pierre Curie and Marie Curie  

Discovery
In 1900  
In 1898  

Abundance
  
  

Abundance In Universe
0.00 %  
17
0.00 %  
40

Abundance In Sun
0.00 %  
26
-  

Abundance In Meteorites
-  
-  

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

Abundance In Oceans
0.00 %  
99+
0.00 %  
99+

Abundance In Humans
0.00 %  
24
0.00 %  
24

Uses

Uses & Benefits
  • Currently known uses of Protactinium metal are limited to research purpose only.
  
  • Polonium metal has different Allotropes, it is used in antistatic devices and for research purpose.
  • A 1 gram of Polonium can reach a temperature of 500°C, hence it is used as a heat source for space equipment.
  

Industrial Uses
-  
Aerospace Industry, Ammunition Industry  

Medical Uses
-  
-  

Other Uses
-  
Alloys  

Biological Properties
  
  

Toxicity
Highly Toxic  
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
254.00 °C  
99+

Boiling Point
4,027.00 °C  
12
962.00 °C  
99+

Appearance
  
  

Physical State
Solid  
Solid  

Color
Silver  
Silver  

Luster
Metallic  
-  

Hardness
  
  

Mohs Hardness
5.00  
8
2.50  
15

Brinell Hardness
125.00 MPa  
99+
70.00 MPa  
99+

Vickers Hardness
220.00 MPa  
99+
30.00 MPa  
99+

Speed of Sound
12,400.00 m/s  
3
2,260.00 m/s  
99+

Optical Properties
  
  

Refractive Index
1.60  
33
2.70  
3

Reflectivity
60.00 %  
23
50.00 %  
31

Allotropes
No  
Yes  

α Allotropes
-  
α-polonium  

β Allotropes
-  
β-polonium  

γ Allotropes
-  
-  

Chemical

Chemical Formula
Pa  
Po  

Isotopes
  
  

Known Isotopes
27  
12
29  
10

Electronegativity
  
  

Pauling Electronegativity
1.50  
28
2.00  
8

Sanderson Electronegativity
1.50  
18
2.00  
10

Allred Rochow Electronegativity
1.14  
29
1.76  
3

Mulliken-Jaffe Electronegativity
1.50  
26
2.48  
1

Allen Electronegativity
1.50  
32
2.19  
2

Electropositivity
  
  

Pauling Electropositivity
2.50  
27
2.00  
99+

Ionization Energies
  
  

1st Energy Level
568.00 kJ/mol  
99+
812.10 kJ/mol  
14

2nd Energy Level
1,128.00 kJ/mol  
99+
1,833.20 kJ/mol  
17

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

4th Energy Level
2,991.00 kJ/mol  
99+
8,121.00 kJ/mol  
7

5th Energy Level
5,120.00 kJ/mol  
99+
8,120.00 kJ/mol  
12

6th Energy Level
5,680.00 kJ/mol  
99+
8,120.00 kJ/mol  
32

7th Energy level
5,680.00 kJ/mol  
99+
8,120.00 kJ/mol  
26

8th Energy Level
5,680.00 kJ/mol  
99+
8,120.00 kJ/mol  
26

9th Energy Level
5,120.00 kJ/mol  
99+
8,120.00 kJ/mol  
23

10th Energy Level
5,120.00 kJ/mol  
99+
8,120.00 kJ/mol  
27

11th Energy Level
5,680.00 kJ/mol  
99+
8,120.00 kJ/mol  
26

12th Energy Level
5,680.00 kJ/mol  
99+
8,120.00 kJ/mol  
99+

13th Energy Level
5,680.00 kJ/mol  
99+
8,120.00 kJ/mol  
19

14th Energy Level
5,680.00 kJ/mol  
99+
8,120.00 kJ/mol  
18

15th Energy Level
56,800.00 kJ/mol  
99+
81,200.00 kJ/mol  
15

16th Energy Level
56,800.00 kJ/mol  
99+
81,200.00 kJ/mol  
12

17th Energy Level
568.50 kJ/mol  
99+
812.10 kJ/mol  
32

18th Energy Level
5,680.00 kJ/mol  
99+
8,120.00 kJ/mol  
21

19th Energy Level
568.30 kJ/mol  
99+
812.10 kJ/mol  
29

20th Energy Level
568.00 kJ/mol  
99+
812.00 kJ/mol  
22

21st Energy Level
568.00 kJ/mol  
99+
812.10 kJ/mol  
40

22nd Energy Level
568.00 kJ/mol  
99+
812.00 kJ/mol  
17

23rd Energy Level
568.00 kJ/mol  
99+
812.10 kJ/mol  
99+

24th Energy Level
568.00 kJ/mol  
99+
812.10 kJ/mol  
13

25th Energy Level
568.00 kJ/mol  
99+
812.10 kJ/mol  
11

26th Energy Level
568.00 kJ/mol  
99+
812.10 kJ/mol  
11

27th Energy Level
568.00 kJ/mol  
99+
812.10 kJ/mol  
10

28th Energy Level
568.00 kJ/mol  
99+
812.10 kJ/mol  
16

29th Energy Level
568.00 kJ/mol  
99+
812.10 kJ/mol  
15

30th Energy Level
568.00 kJ/mol  
99+
812.00 kJ/mol  
11

Electrochemical Equivalent
1.72 g/amp-hr  
99+
3.90 g/amp-hr  
8

Electron Work Function
5.89 eV  
3
4.50 eV  
19

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

Atomic

Atomic Number
91  
27
84  
32

Electron Configuration
[Rn] 5f2 6d1 7s2  
[Xe] 4f14 5d10 6s2 6p4  

Crystal Structure
Tetragonal (TETR)  
Monoclinic (MON)  

Crystal Lattice
TETR-Crystal-Structure-of-Protactinium.jpg#100  
MON-Crystal-Structure-of-Polonium.jpg#100  

Atom
  
  

Number of Protons
91  
27
84  
32

Number of Neutrons
122  
22
125  
20

Number of Electrons
91  
27
84  
32

Radius of an Atom
  
  

Atomic Radius
163.00 pm  
27
168.00 pm  
25

Covalent Radius
200.00 pm  
11
140.00 pm  
99+

Van der Waals Radius
243.00 pm  
15
197.00 pm  
36

Atomic Weight
231.04 amu  
24
209.00 amu  
28

Atomic Volume
15.00 cm3/mol  
99+
22.23 cm3/mol  
22

Adjacent Atomic Numbers
  
  

Previous Element
Thorium
  
Bismuth
  

Next Element
Uranium
  
Francium
  

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

Lattice Constant
392.50 pm  
26
335.90 pm  
99+

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

Lattice C/A Ratio
1.58  
36
1.46  
99+

Mechanical

Density
  
  

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

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

Tensile Strength
80.00 MPa  
29
50.00 MPa  
38

Viscosity
0.00  
25
0.00  
26

Vapor Pressure
  
  

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

Vapor Pressure at 2000 K
0.00 (Pa)  
32
0.00 (Pa)  
37

Elasticity properties
  
  

Shear Modulus
16.00 GPa  
99+
24.00 GPa  
40

Bulk Modulus
47.00 GPa  
26
46.00 GPa  
28

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

Poisson Ratio
0.23  
30
0.23  
30

Other Mechanical Properties
-  
-  

Magnetic

Magnetic Characteristics
  
  

Specific Gravity
15.37  
23
9.32  
99+

Magnetic Ordering
Paramagnetic  
Nonmagnetic  

Permeability
0.00 H/m  
10
0.00 H/m  
15

Susceptibility
0.00  
21
0.00  
24

Electrical Properties
  
  

Electrical Property
Conductor  
Conductor  

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

Electrical Conductivity
0.05 106/cm Ω  
39
0.02 106/cm Ω  
99+

Electron Affinity
53.03 kJ/mol  
22
183.30 kJ/mol  
3

Thermal

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

Molar Heat Capacity
27.20 J/mol·K  
24
26.40 J/mol·K  
36

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

Critical Temperature
1,841.00 K  
25
527.00 K  
99+

Thermal Expansion
9.90 µm/(m·K)  
99+
23.50 µm/(m·K)  
16

Enthalpy
  
  

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

Enthalpy of Fusion
12.34 kJ/mol  
34
13.00 kJ/mol  
32

Enthalpy of Atomization
481.90 kJ/mol  
19
134.00 kJ/mol  
99+

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

Summary >>
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Actinide Series

Actinide Series

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