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Protactinium vs Cerium


Cerium vs Protactinium


Periodic Table

Symbol
Pa  
Ce  

Group Number
3  
15
3  
15

Period Number
7  
6  

Block
f block  
f block  

Element Family
Actinide  
Lanthanide  

CAS Number
7440133  
99+
7440451  
99+

Space Group Name
I4/mmm  
P63/mmc  

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.
  
  • Cerium is a rare earth metal but still it is not rare at all.
  • It’s non-toxic compound Cerium sulfide has a rich red color and it is used as a pigment.
  • Cerium metal is also used in Flat screen TVs, light bulb, floodlights, etc.
  

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

History
  
  

Who Discovered
William Crookes  
Martin Heinrich Klaproth, Jöns Jakob Berzelius, Wilhelm Hisinger  

Discovery
In 1900  
In 1803  

Abundance
  
  

Abundance In Universe
0.00 %  
17
0.00 %  
17

Abundance In Sun
0.00 %  
26
0.00 %  
23

Abundance In Meteorites
-  
0.00 %  
27

Abundance In Earth's Crust
0.00 %  
99+
0.01 %  
18

Abundance In Oceans
0.00 %  
99+
0.00 %  
33

Abundance In Humans
0.00 %  
24
0.00 %  
24

Uses

Uses & Benefits
  • Currently known uses of Protactinium metal are limited to research purpose only.
  
  • It is used to include flints for cigarette lighters.
  • Its compound Cerium (Ill) Oxide is used as a catalyst; it is put inside the walls of the oven as it prevents from the buildup of cooking residues.
  

Industrial Uses
-  
Chemical Industry  

Medical Uses
-  
Medical Research  

Other Uses
-  
Alloys  

Biological Properties
  
  

Toxicity
Highly Toxic  
Moderately Toxic  

Present in Human Body
No  
Yes  

In Blood
0.00 Blood/mg dm-3  
40
0.00 Blood/mg dm-3  
30

In Bone
0.00 p.p.m.  
99+
2.70 p.p.m.  
14

Physical

Melting Point
1,568.00 °C  
21
795.00 °C  
99+

Boiling Point
4,027.00 °C  
12
3,257.00 °C  
24

Appearance
  
  

Physical State
Solid  
Solid  

Color
Silver  
Silvery White  

Luster
Metallic  
Lustrous  

Hardness
  
  

Mohs Hardness
5.00  
8
2.50  
15

Brinell Hardness
125.00 MPa  
99+
186.00 MPa  
99+

Vickers Hardness
220.00 MPa  
99+
210.00 MPa  
99+

Speed of Sound
12,400.00 m/s  
3
2,100.00 m/s  
99+

Optical Properties
  
  

Refractive Index
1.60  
33
2.20  
9

Reflectivity
60.00 %  
23
68.00 %  
15

Allotropes
No  
No  

α Allotropes
-  
-  

β Allotropes
-  
-  

γ Allotropes
-  
-  

Chemical

Chemical Formula
Pa  
Ce  

Isotopes
  
  

Known Isotopes
27  
12
30  
9

Electronegativity
  
  

Pauling Electronegativity
1.50  
28
1.12  
99+

Sanderson Electronegativity
1.50  
18
1.12  
37

Allred Rochow Electronegativity
1.14  
29
1.08  
32

Mulliken-Jaffe Electronegativity
1.50  
26
1.12  
99+

Allen Electronegativity
1.50  
32
1.12  
99+

Electropositivity
  
  

Pauling Electropositivity
2.50  
27
2.88  
11

Ionization Energies
  
  

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

2nd Energy Level
1,128.00 kJ/mol  
99+
1,050.00 kJ/mol  
99+

3rd Energy Level
1,814.00 kJ/mol  
99+
1,949.00 kJ/mol  
99+

4th Energy Level
2,991.00 kJ/mol  
99+
3,547.00 kJ/mol  
99+

5th Energy Level
5,120.00 kJ/mol  
99+
6,325.00 kJ/mol  
37

6th Energy Level
5,680.00 kJ/mol  
99+
7,490.00 kJ/mol  
38

7th Energy level
5,680.00 kJ/mol  
99+
5,340.00 kJ/mol  
99+

8th Energy Level
5,680.00 kJ/mol  
99+
5,340.00 kJ/mol  
99+

9th Energy Level
5,120.00 kJ/mol  
99+
5,340.00 kJ/mol  
99+

10th Energy Level
5,120.00 kJ/mol  
99+
5,340.00 kJ/mol  
99+

11th Energy Level
5,680.00 kJ/mol  
99+
5,340.00 kJ/mol  
99+

12th Energy Level
5,680.00 kJ/mol  
99+
5,340.00 kJ/mol  
99+

13th Energy Level
5,680.00 kJ/mol  
99+
5,650.00 kJ/mol  
99+

14th Energy Level
5,680.00 kJ/mol  
99+
5,340.00 kJ/mol  
99+

15th Energy Level
56,800.00 kJ/mol  
99+
53,400.00 kJ/mol  
99+

16th Energy Level
56,800.00 kJ/mol  
99+
53,400.00 kJ/mol  
99+

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

18th Energy Level
5,680.00 kJ/mol  
99+
5,340.00 kJ/mol  
99+

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

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

21st Energy Level
568.00 kJ/mol  
99+
5,346.00 kJ/mol  
24

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

23rd Energy Level
568.00 kJ/mol  
99+
5,346.00 kJ/mol  
26

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

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

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

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

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

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

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

Electrochemical Equivalent
1.72 g/amp-hr  
99+
1.74 g/amp-hr  
99+

Electron Work Function
5.89 eV  
3
2.84 eV  
99+

Other Chemical Properties
Ionization, Radioactive Isotopes, Radioactivity  
Chemical Stability, Anti Corrosion, Ionization, Radioactive Isotopes, Solubility  

Atomic

Atomic Number
91  
27
58  
99+

Electron Configuration
[Rn] 5f2 6d1 7s2  
[Xe] 4f1 5d1 6s2  

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

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

Atom
  
  

Number of Protons
91  
27
58  
99+

Number of Neutrons
122  
22
82  
99+

Number of Electrons
91  
27
58  
99+

Radius of an Atom
  
  

Atomic Radius
163.00 pm  
27
181.80 pm  
14

Covalent Radius
200.00 pm  
11
204.00 pm  
8

Van der Waals Radius
243.00 pm  
15
235.00 pm  
21

Atomic Weight
231.04 amu  
24
140.12 amu  
99+

Atomic Volume
15.00 cm3/mol  
99+
20.67 cm3/mol  
27

Adjacent Atomic Numbers
  
  

Previous Element
Thorium
  
Lanthanum
  

Next Element
Uranium
  

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

Lattice Constant
392.50 pm  
26
362.00 pm  
38

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

Lattice C/A Ratio
1.58  
36
1.59  
31

Mechanical

Density
  
  

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

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

Tensile Strength
80.00 MPa  
29
270.00 MPa  
17

Viscosity
0.00  
25
0.00  
23

Vapor Pressure
  
  

Vapor Pressure at 1000 K
0.00 (Pa)  
37
0.00 (Pa)  
36

Vapor Pressure at 2000 K
0.00 (Pa)  
32
1.04 (Pa)  
13

Elasticity properties
  
  

Shear Modulus
16.00 GPa  
99+
13.50 GPa  
99+

Bulk Modulus
47.00 GPa  
26
21.50 GPa  
99+

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

Poisson Ratio
0.23  
30
0.24  
27

Other Mechanical Properties
-  
Ductile, Malleable  

Magnetic

Magnetic Characteristics
  
  

Specific Gravity
15.37  
23
6.77  
99+

Magnetic Ordering
Paramagnetic  
Paramagnetic  

Permeability
0.00 H/m  
10
0.00 H/m  
7

Susceptibility
0.00  
21
0.00  
24

Electrical Properties
  
  

Electrical Property
Conductor  
Conductor  

Resistivity
177.00 nΩ·m  
21
828.00 nΩ·m  
3

Electrical Conductivity
0.05 106/cm Ω  
39
0.01 106/cm Ω  
99+

Electron Affinity
53.03 kJ/mol  
22
50.00 kJ/mol  
26

Thermal

Specific Heat
0.12 J/(kg K)  
99+
0.19 J/(kg K)  
33

Molar Heat Capacity
27.20 J/mol·K  
24
26.94 J/mol·K  
30

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

Critical Temperature
1,841.00 K  
25
1,071.00 K  
99+

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

Enthalpy
  
  

Enthalpy of Vaporization
481.00 kJ/mol  
17
414.00 kJ/mol  
22

Enthalpy of Fusion
12.34 kJ/mol  
34
5.46 kJ/mol  
99+

Enthalpy of Atomization
481.90 kJ/mol  
19
381.00 kJ/mol  
31

Standard Molar Entropy
198.10 J/mol.K  
1
72.00 J/mol.K  
12

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