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Americium Protactinium Comparison


Protactinium Americium comparison


Periodic Table

Symbol
Am  
Pa  

Group Number
10  
8
3  
15

Period Number
7  
7  

Block
f block  
f block  

Element Family
Actinide  
Actinide  

CAS Number
7440359  
99+
7440133  
99+

Space Group Name
P63/mmc  
I4/mmm  

Space Group Number
194.00  
7
139.00  
11

Facts

Interesting Facts
  • Americium metal is produced by bombarding Plutonium with Neutrons.
  • Americium metal was discovered as a by-product while testing an atomic bomb (Manhattan Project).
  
  • Protactinium metal has 29 isotopes.
  • Isotopes of Protactinium-231 used in nuclear weapon.
  

Sources
Obtained By Bombarding Plutonium with Neutrons  
Found in Uranium Ores, Mining, Ores of metals  

History
  
  

Who Discovered
Glenn T. Seaborg, Ralph A. James, Leon O. Morgan, Albert Ghiorso  
William Crookes  

Discovery
In 1944  
In 1900  

Abundance
  
  

Abundance In Universe
0.00 %  
35
0.00 %  
17

Abundance In Sun
0.00 %  
30
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+

Abundance In Humans
0.00 %  
24
0.00 %  
24

Uses

Uses & Benefits
  • Americium metal is used in smoke detection alarms.
  • In the future, this metal has a potential to be used in batteries of spacecrafts.
  
  • 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
994.00 °C  
99+
1,568.00 °C  
21

Boiling Point
2,607.00 °C  
99+
4,027.00 °C  
12

Appearance
  
  

Physical State
Solid  
Solid  

Color
Silvery White  
Silver  

Luster
-  
Metallic  

Hardness
  
  

Mohs Hardness
6.00  
6
5.00  
8

Brinell Hardness
260.00 MPa  
99+
125.00 MPa  
99+

Vickers Hardness
600.00 MPa  
28
220.00 MPa  
99+

Speed of Sound
2,750.00 m/s  
99+
12,400.00 m/s  
3

Optical Properties
  
  

Refractive Index
1.30  
99+
1.60  
33

Reflectivity
64.00 %  
19
60.00 %  
23

Allotropes
No  
No  

α Allotropes
-  
-  

β Allotropes
-  
-  

γ Allotropes
-  
-  

Chemical

Chemical Formula
Am  
Pa  

Isotopes
  
  

Known Isotopes
16  
23
27  
12

Electronegativity
  
  

Pauling Electronegativity
1.30  
33
1.50  
28

Sanderson Electronegativity
1.30  
25
1.50  
18

Allred Rochow Electronegativity
1.20  
28
1.14  
29

Mulliken-Jaffe Electronegativity
1.30  
33
1.50  
26

Allen Electronegativity
1.30  
40
1.50  
32

Electropositivity
  
  

Pauling Electropositivity
2.70  
22
2.50  
27

Ionization Energies
  
  

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

2nd Energy Level
1,158.00 kJ/mol  
99+
1,128.00 kJ/mol  
99+

3rd Energy Level
2,132.00 kJ/mol  
99+
1,814.00 kJ/mol  
99+

4th Energy Level
3,493.00 kJ/mol  
99+
2,991.00 kJ/mol  
99+

5th Energy Level
5,780.00 kJ/mol  
99+
5,120.00 kJ/mol  
99+

6th Energy Level
5,780.00 kJ/mol  
99+
5,680.00 kJ/mol  
99+

7th Energy level
5,780.00 kJ/mol  
99+
5,680.00 kJ/mol  
99+

8th Energy Level
5,780.00 kJ/mol  
99+
5,680.00 kJ/mol  
99+

9th Energy Level
5,780.00 kJ/mol  
99+
5,120.00 kJ/mol  
99+

10th Energy Level
5,780.00 kJ/mol  
99+
5,120.00 kJ/mol  
99+

11th Energy Level
5,780.00 kJ/mol  
99+
5,680.00 kJ/mol  
99+

12th Energy Level
62,400.00 kJ/mol  
11
5,680.00 kJ/mol  
99+

13th Energy Level
5,780.00 kJ/mol  
99+
5,680.00 kJ/mol  
99+

14th Energy Level
5,780.00 kJ/mol  
99+
5,680.00 kJ/mol  
99+

15th Energy Level
62,400.00 kJ/mol  
39
56,800.00 kJ/mol  
99+

16th Energy Level
57,800.00 kJ/mol  
99+
56,800.00 kJ/mol  
99+

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

18th Energy Level
5,780.00 kJ/mol  
99+
5,680.00 kJ/mol  
99+

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

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

21st Energy Level
5,780.00 kJ/mol  
22
568.00 kJ/mol  
99+

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

23rd Energy Level
5,780.00 kJ/mol  
23
568.00 kJ/mol  
99+

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

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

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

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

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

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

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

Electrochemical Equivalent
3.02 g/amp-hr  
20
1.72 g/amp-hr  
99+

Electron Work Function
4.30 eV  
25
5.89 eV  
3

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

Atomic

Atomic Number
95  
23
91  
27

Electron Configuration
[Rn] 5f7 7s2  
[Rn] 5f2 6d1 7s2  

Crystal Structure
Double Hexagonal Close Packed (DHCP)  
Tetragonal (TETR)  

Crystal Lattice
DHCP-Crystal-Structure-of-Americium.jpg#100  
TETR-Crystal-Structure-of-Protactinium.jpg#100  

Atom
  
  

Number of Protons
95  
23
91  
27

Number of Neutrons
148  
13
122  
22

Number of Electrons
95  
23
91  
27

Radius of an Atom
  
  

Atomic Radius
173.00 pm  
23
163.00 pm  
27

Covalent Radius
180.00 pm  
23
200.00 pm  
11

Van der Waals Radius
244.00 pm  
14
243.00 pm  
15

Atomic Weight
243.00 amu  
20
231.04 amu  
24

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

Adjacent Atomic Numbers
  
  

Previous Element
Plutonium
  
Thorium
  

Next Element
Curium
  
Uranium
  

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

Lattice Constant
346.81 pm  
99+
392.50 pm  
26

Lattice Angles
π/2, π/2, 2 π/3  
π/2, π/2, π/2  

Lattice C/A Ratio
1.58  
34
1.58  
36

Mechanical

Density
  
  

Density At Room Temperature
12.00 g/cm3  
32
15.37 g/cm3  
20

Density When Liquid (at m.p.)
13.67 g/cm3  
26
15.37 g/cm3  
21

Tensile Strength
80.00 MPa  
29
80.00 MPa  
29

Viscosity
0.00  
25
0.00  
25

Vapor Pressure
  
  

Vapor Pressure at 1000 K
0.00 (Pa)  
13
0.00 (Pa)  
37

Vapor Pressure at 2000 K
0.00 (Pa)  
24
0.00 (Pa)  
32

Elasticity properties
  
  

Shear Modulus
26.00 GPa  
36
16.00 GPa  
99+

Bulk Modulus
44.00 GPa  
32
47.00 GPa  
26

Young's Modulus
58.00 GPa  
36
47.00 GPa  
99+

Poisson Ratio
0.30  
14
0.23  
30

Other Mechanical Properties
-  
-  

Magnetic

Magnetic Characteristics
  
  

Specific Gravity
13.67  
26
15.37  
23

Magnetic Ordering
Paramagnetic  
Paramagnetic  

Permeability
0.00 H/m  
16
0.00 H/m  
10

Susceptibility
0.00  
24
0.00  
21

Electrical Properties
  
  

Electrical Property
-  
Conductor  

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

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

Electron Affinity
63.90 kJ/mol  
18
53.03 kJ/mol  
22

Thermal

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

Molar Heat Capacity
62.70 J/mol·K  
1
27.20 J/mol·K  
24

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

Critical Temperature
1,449.00 K  
99+
1,841.00 K  
25

Thermal Expansion
13.60 µm/(m·K)  
32
9.90 µm/(m·K)  
99+

Enthalpy
  
  

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

Enthalpy of Fusion
14.39 kJ/mol  
27
12.34 kJ/mol  
34

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

Standard Molar Entropy
63.10 J/mol.K  
23
198.10 J/mol.K  
1

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