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Actinium vs Protactinium


Protactinium vs Actinium


Periodic Table

Symbol
Ac  
Pa  

Group Number
3  
15
3  
15

Period Number
7  
7  

Block
f block  
f block  

Element Family
Actinide  
Actinide  

CAS Number
7440348  
99+
7440133  
99+

Space Group Name
Fm_ 3m  
I4/mmm  

Space Group Number
225.00  
3
139.00  
11

Facts

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

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

History
  
  

Who Discovered
Friedrich Oskar Giesel  
William Crookes  

Discovery
In 1902  
In 1900  

Abundance
  
  

Abundance In Universe
0.00 %  
34
0.00 %  
17

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
  • Actinium metal has a great source of alpha rays but it is hardly used outside research purpose.
  
  • Currently known uses of Protactinium metal are limited to research purpose only.
  

Industrial Uses
-  
-  

Medical Uses
-  
-  

Other Uses
Alloys, Nuclear Research, Research Purposes  
-  

Biological Properties
  
  

Toxicity
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
1,227.00 °C  
38
1,568.00 °C  
21

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

Appearance
  
  

Physical State
Solid  
Solid  

Color
Silvery White  
Silver  

Luster
-  
Metallic  

Hardness
  
  

Mohs Hardness
6.50  
5
5.00  
8

Brinell Hardness
70.00 MPa  
99+
125.00 MPa  
99+

Vickers Hardness
260.00 MPa  
99+
220.00 MPa  
99+

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

Optical Properties
  
  

Refractive Index
1.00  
99+
1.60  
33

Reflectivity
62.00 %  
21
60.00 %  
23

Allotropes
No  
No  

α Allotropes
-  
-  

β Allotropes
-  
-  

γ Allotropes
-  
-  

Chemical

Chemical Formula
Ac  
Pa  

Isotopes
  
  

Known Isotopes
29  
10
27  
12

Electronegativity
  
  

Pauling Electronegativity
1.10  
99+
1.50  
28

Sanderson Electronegativity
1.10  
38
1.50  
18

Allred Rochow Electronegativity
1.00  
37
1.14  
29

Mulliken-Jaffe Electronegativity
1.10  
99+
1.50  
26

Allen Electronegativity
1.10  
99+
1.50  
32

Electropositivity
  
  

Pauling Electropositivity
2.90  
10
2.50  
27

Ionization Energies
  
  

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Electron Work Function
4.38 eV  
23
5.89 eV  
3

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

Atomic

Atomic Number
89  
29
91  
27

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

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

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

Atom
  
  

Number of Protons
89  
29
91  
27

Number of Neutrons
138  
17
122  
22

Number of Electrons
89  
29
91  
27

Radius of an Atom
  
  

Atomic Radius
195.00 pm  
9
163.00 pm  
27

Covalent Radius
186.00 pm  
21
200.00 pm  
11

Van der Waals Radius
215.00 pm  
31
243.00 pm  
15

Atomic Weight
227.00 amu  
25
231.04 amu  
24

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

Adjacent Atomic Numbers
  
  

Previous Element
Radium
  
Thorium
  

Next Element
Thorium
  
Uranium
  

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

Lattice Constant
567.00 pm  
9
392.50 pm  
26

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

Lattice C/A Ratio
1.89  
2
1.58  
36

Mechanical

Density
  
  

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

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

Tensile Strength
65.00 MPa  
33
80.00 MPa  
29

Viscosity
0.00  
25
0.00  
25

Vapor Pressure
  
  

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

Vapor Pressure at 2000 K
0.00 (Pa)  
30
0.00 (Pa)  
32

Elasticity properties
  
  

Shear Modulus
25.00 GPa  
38
16.00 GPa  
99+

Bulk Modulus
94.00 GPa  
17
47.00 GPa  
26

Young's Modulus
130.00 GPa  
16
47.00 GPa  
99+

Poisson Ratio
0.34  
10
0.23  
30

Other Mechanical Properties
-  
-  

Magnetic

Magnetic Characteristics
  
  

Specific Gravity
10.07  
99+
15.37  
23

Magnetic Ordering
Paramagnetic  
Paramagnetic  

Permeability
0.00 H/m  
17
0.00 H/m  
10

Susceptibility
0.00  
24
0.00  
21

Electrical Properties
  
  

Electrical Property
-  
Conductor  

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

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

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

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
12.00 W/m·K  
99+
47.00 W/m·K  
32

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

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

Enthalpy
  
  

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

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

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

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

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Actinide Series

Actinide Series

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