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Protactinium vs Actinium


Actinium vs Protactinium


Periodic Table

Symbol
Pa  
Ac  

Group Number
3  
15
3  
15

Period Number
7  
7  

Block
f block  
f block  

Element Family
Actinide  
Actinide  

CAS Number
7440133  
99+
7440348  
99+

Space Group Name
I4/mmm  
Fm_ 3m  

Space Group Number
139.00  
11
225.00  
3

Facts

Interesting Facts
  • Protactinium metal has 29 isotopes.
  • Isotopes of Protactinium-231 used in nuclear weapon.
  
Actinium glows in the dark due to its radioactivity.  

Sources
Found in Uranium Ores, Mining, Ores of metals  
Obtained by Treating Radium with Neutrons, Ores of metals  

History
  
  

Who Discovered
William Crookes  
Friedrich Oskar Giesel  

Discovery
In 1900  
In 1902  

Abundance
  
  

Abundance In Universe
0.00 %  
17
0.00 %  
34

Abundance In Sun
0.00 %  
26
0.00 %  
26

Abundance In Meteorites
-  
0.00 %  
99+

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.
  
  • Actinium metal has a great source of alpha rays but it is hardly used outside research purpose.
  

Industrial Uses
-  
-  

Medical Uses
-  
-  

Other Uses
-  
Alloys, Nuclear Research, Research Purposes  

Biological Properties
  
  

Toxicity
Highly Toxic  
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
1,227.00 °C  
38

Boiling Point
4,027.00 °C  
12
3,200.00 °C  
27

Appearance
  
  

Physical State
Solid  
Solid  

Color
Silver  
Silvery White  

Luster
Metallic  
-  

Hardness
  
  

Mohs Hardness
5.00  
8
6.50  
5

Brinell Hardness
125.00 MPa  
99+
70.00 MPa  
99+

Vickers Hardness
220.00 MPa  
99+
260.00 MPa  
99+

Speed of Sound
12,400.00 m/s  
3
3,430.00 m/s  
32

Optical Properties
  
  

Refractive Index
1.60  
33
1.00  
99+

Reflectivity
60.00 %  
23
62.00 %  
21

Allotropes
No  
No  

α Allotropes
-  
-  

β Allotropes
-  
-  

γ Allotropes
-  
-  

Chemical

Chemical Formula
Pa  
Ac  

Isotopes
  
  

Known Isotopes
27  
12
29  
10

Electronegativity
  
  

Pauling Electronegativity
1.50  
28
1.10  
99+

Sanderson Electronegativity
1.50  
18
1.10  
38

Allred Rochow Electronegativity
1.14  
29
1.00  
37

Mulliken-Jaffe Electronegativity
1.50  
26
1.10  
99+

Allen Electronegativity
1.50  
32
1.10  
99+

Electropositivity
  
  

Pauling Electropositivity
2.50  
27
2.90  
10

Ionization Energies
  
  

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

2nd Energy Level
1,128.00 kJ/mol  
99+
1,170.00 kJ/mol  
99+

3rd Energy Level
1,814.00 kJ/mol  
99+
1,900.00 kJ/mol  
99+

4th Energy Level
2,991.00 kJ/mol  
99+
4,700.00 kJ/mol  
33

5th Energy Level
5,120.00 kJ/mol  
99+
4,990.00 kJ/mol  
99+

6th Energy Level
5,680.00 kJ/mol  
99+
5,750.00 kJ/mol  
99+

7th Energy level
5,680.00 kJ/mol  
99+
5,750.00 kJ/mol  
99+

8th Energy Level
5,680.00 kJ/mol  
99+
5,750.00 kJ/mol  
99+

9th Energy Level
5,120.00 kJ/mol  
99+
4,990.00 kJ/mol  
99+

10th Energy Level
5,120.00 kJ/mol  
99+
4,990.00 kJ/mol  
99+

11th Energy Level
5,680.00 kJ/mol  
99+
4,990.00 kJ/mol  
99+

12th Energy Level
5,680.00 kJ/mol  
99+
49,900.00 kJ/mol  
21

13th Energy Level
5,680.00 kJ/mol  
99+
4,990.00 kJ/mol  
99+

14th Energy Level
5,680.00 kJ/mol  
99+
4,990.00 kJ/mol  
99+

15th Energy Level
56,800.00 kJ/mol  
99+
49,900.00 kJ/mol  
99+

16th Energy Level
56,800.00 kJ/mol  
99+
49,900.00 kJ/mol  
99+

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

18th Energy Level
5,680.00 kJ/mol  
99+
4,990.00 kJ/mol  
99+

19th Energy Level
568.30 kJ/mol  
99+
499.00 kJ/mol  
99+

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

21st Energy Level
568.00 kJ/mol  
99+
4,990.00 kJ/mol  
25

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

23rd Energy Level
568.00 kJ/mol  
99+
4,990.00 kJ/mol  
29

24th Energy Level
568.00 kJ/mol  
99+
499.00 kJ/mol  
99+

25th Energy Level
568.00 kJ/mol  
99+
499.00 kJ/mol  
99+

26th Energy Level
568.00 kJ/mol  
99+
499.00 kJ/mol  
99+

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

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

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

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

Electrochemical Equivalent
1.72 g/amp-hr  
99+
2.82 g/amp-hr  
22

Electron Work Function
5.89 eV  
3
4.38 eV  
23

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

Atomic

Atomic Number
91  
27
89  
29

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

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

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

Atom
  
  

Number of Protons
91  
27
89  
29

Number of Neutrons
122  
22
138  
17

Number of Electrons
91  
27
89  
29

Radius of an Atom
  
  

Atomic Radius
163.00 pm  
27
195.00 pm  
9

Covalent Radius
200.00 pm  
11
186.00 pm  
21

Van der Waals Radius
243.00 pm  
15
215.00 pm  
31

Atomic Weight
231.04 amu  
24
227.00 amu  
25

Atomic Volume
15.00 cm3/mol  
99+
22.54 cm3/mol  
20

Adjacent Atomic Numbers
  
  

Previous Element
Thorium
  
Radium
  

Next Element
Uranium
  
Thorium
  

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

Lattice Constant
392.50 pm  
26
567.00 pm  
9

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

Lattice C/A Ratio
1.58  
36
1.89  
2

Mechanical

Density
  
  

Density At Room Temperature
15.37 g/cm3  
20
10.00 g/cm3  
40

Density When Liquid (at m.p.)
15.37 g/cm3  
21
10.07 g/cm3  
40

Tensile Strength
80.00 MPa  
29
65.00 MPa  
33

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+
25.00 GPa  
38

Bulk Modulus
47.00 GPa  
26
94.00 GPa  
17

Young's Modulus
47.00 GPa  
99+
130.00 GPa  
16

Poisson Ratio
0.23  
30
0.34  
10

Other Mechanical Properties
-  
-  

Magnetic

Magnetic Characteristics
  
  

Specific Gravity
15.37  
23
10.07  
99+

Magnetic Ordering
Paramagnetic  
Paramagnetic  

Permeability
0.00 H/m  
10
0.00 H/m  
17

Susceptibility
0.00  
21
0.00  
24

Electrical Properties
  
  

Electrical Property
Conductor  
-  

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

Electrical Conductivity
0.05 106/cm Ω  
39
0.15 106/cm Ω  
13

Electron Affinity
53.03 kJ/mol  
22
33.20 kJ/mol  
34

Thermal

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

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

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

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

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

Enthalpy
  
  

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

Enthalpy of Fusion
12.34 kJ/mol  
34
14.20 kJ/mol  
28

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

Standard Molar Entropy
198.10 J/mol.K  
1
56.50 J/mol.K  
33

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Actinide Series

Actinide Series

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