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Hafnium vs Actinium


Actinium vs Hafnium


Periodic Table

Symbol
Hf  
Ac  

Group Number
4  
14
3  
15

Period Number
6  
7  

Block
d block  
f block  

Element Family
Transition Metal  
Actinide  

CAS Number
7440586  
30
7440348  
99+

Space Group Name
P63/mmc  
Fm_ 3m  

Space Group Number
194.00  
7
225.00  
3

Facts

Interesting Facts
  • Hafnium metal is highly reactive, hence not found free in nature.
  • Hafnium metal as predicated after Mendeleev finished his periodic table.
  
Actinium glows in the dark due to its radioactivity.  

Sources
By-product Zirconium Refining  
Obtained by Treating Radium with Neutrons, Ores of metals  

History
  
  

Who Discovered
Dirk Coster and George de Hevesy  
Friedrich Oskar Giesel  

Discovery
In 1922  
In 1902  

Abundance
  
  

Abundance In Universe
0.00 %  
26
0.00 %  
34

Abundance In Sun
0.00 %  
26
0.00 %  
26

Abundance In Meteorites
0.00 %  
37
0.00 %  
99+

Abundance In Earth's Crust
0.00 %  
31
0.00 %  
99+

Abundance In Oceans
0.00 %  
27
0.00 %  
99+

Abundance In Humans
0.00 %  
14
0.00 %  
24

Uses

Uses & Benefits
  • It has an ability to absorb neutrons and hence it is used to make control rods in nuclear submarines. And this metal is also used in Plasma welding torches.
  • It alloys with iron, titanium and niobium are very useful.
  
  • Actinium metal has a great source of alpha rays but it is hardly used outside research purpose.
  

Industrial Uses
Ammunition Industry  
-  

Medical Uses
-  
-  

Other Uses
Alloys, In Nuclear Reactors, Nuclear Research, Research Purposes  
Alloys, Nuclear Research, Research Purposes  

Biological Properties
  
  

Toxicity
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
2,150.00 °C  
10
1,227.00 °C  
38

Boiling Point
5,400.00 °C  
5
3,200.00 °C  
27

Appearance
  
  

Physical State
Solid  
Solid  

Color
Gray  
Silvery White  

Luster
Metallic  
-  

Hardness
  
  

Mohs Hardness
5.50  
7
6.50  
5

Brinell Hardness
1,450.00 MPa  
6
70.00 MPa  
99+

Vickers Hardness
1,520.00 MPa  
10
260.00 MPa  
99+

Speed of Sound
3,010.00 m/s  
39
3,430.00 m/s  
32

Optical Properties
  
  

Refractive Index
2.00  
15
1.00  
99+

Reflectivity
71.00 %  
12
62.00 %  
21

Allotropes
No  
No  

α Allotropes
-  
-  

β Allotropes
-  
-  

γ Allotropes
-  
-  

Chemical

Chemical Formula
Hf  
Ac  

Isotopes
  
  

Known Isotopes
32  
7
29  
10

Electronegativity
  
  

Pauling Electronegativity
1.30  
33
1.10  
99+

Sanderson Electronegativity
1.30  
25
1.10  
38

Allred Rochow Electronegativity
1.23  
26
1.00  
37

Mulliken-Jaffe Electronegativity
1.30  
33
1.10  
99+

Allen Electronegativity
1.16  
99+
1.10  
99+

Electropositivity
  
  

Pauling Electropositivity
2.70  
22
2.90  
10

Ionization Energies
  
  

1st Energy Level
658.50 kJ/mol  
40
499.00 kJ/mol  
99+

2nd Energy Level
1,440.00 kJ/mol  
99+
1,170.00 kJ/mol  
99+

3rd Energy Level
2,250.00 kJ/mol  
99+
1,900.00 kJ/mol  
99+

4th Energy Level
3,216.00 kJ/mol  
99+
4,700.00 kJ/mol  
33

5th Energy Level
6,585.00 kJ/mol  
33
4,990.00 kJ/mol  
99+

6th Energy Level
6,585.00 kJ/mol  
99+
5,750.00 kJ/mol  
99+

7th Energy level
6,580.00 kJ/mol  
99+
5,750.00 kJ/mol  
99+

8th Energy Level
6,580.00 kJ/mol  
99+
5,750.00 kJ/mol  
99+

9th Energy Level
6,585.00 kJ/mol  
38
4,990.00 kJ/mol  
99+

10th Energy Level
6,590.00 kJ/mol  
40
4,990.00 kJ/mol  
99+

11th Energy Level
6,585.00 kJ/mol  
40
4,990.00 kJ/mol  
99+

12th Energy Level
6,580.00 kJ/mol  
99+
49,900.00 kJ/mol  
21

13th Energy Level
6,580.00 kJ/mol  
35
4,990.00 kJ/mol  
99+

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

15th Energy Level
65,800.00 kJ/mol  
34
49,900.00 kJ/mol  
99+

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

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

18th Energy Level
6,585.00 kJ/mol  
36
4,990.00 kJ/mol  
99+

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

20th Energy Level
658.00 kJ/mol  
37
499.00 kJ/mol  
99+

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

22nd Energy Level
658.00 kJ/mol  
31
499.00 kJ/mol  
99+

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

24th Energy Level
658.50 kJ/mol  
31
499.00 kJ/mol  
99+

25th Energy Level
658.00 kJ/mol  
33
499.00 kJ/mol  
99+

26th Energy Level
658.50 kJ/mol  
32
499.00 kJ/mol  
99+

27th Energy Level
658.50 kJ/mol  
33
499.00 kJ/mol  
99+

28th Energy Level
658.50 kJ/mol  
38
499.00 kJ/mol  
99+

29th Energy Level
658.50 kJ/mol  
39
499.00 kJ/mol  
99+

30th Energy Level
658.00 kJ/mol  
35
499.00 kJ/mol  
99+

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

Electron Work Function
3.90 eV  
36
4.38 eV  
23

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

Atomic

Atomic Number
72  
99+
89  
29

Electron Configuration
[Xe] 4f14 5d2 6s2  
[Rn] 6d1 7s2  

Crystal Structure
Hexagonal Close Packed (HCP)  
Face Centered Cubic (FCC)  

Crystal Lattice
BCC-Crystal-Structure-.jpg#100  
FCC-Crystal-Structure-of-Actinium.jpg#100  

Atom
  
  

Number of Protons
72  
99+
89  
29

Number of Neutrons
106  
30
138  
17

Number of Electrons
72  
99+
89  
29

Radius of an Atom
  
  

Atomic Radius
159.00 pm  
30
195.00 pm  
9

Covalent Radius
175.00 pm  
25
186.00 pm  
21

Van der Waals Radius
200.00 pm  
35
215.00 pm  
31

Atomic Weight
178.49 amu  
39
227.00 amu  
25

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

Adjacent Atomic Numbers
  
  

Previous Element
Lutetium
  
Radium
  

Next Element
Tantalum
  
Thorium
  

Valence Electron Potential
81.00 (-eV)  
16
38.60 (-eV)  
99+

Lattice Constant
319.64 pm  
99+
567.00 pm  
9

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

Lattice C/A Ratio
1.58  
34
1.89  
2

Mechanical

Density
  
  

Density At Room Temperature
13.31 g/cm3  
27
10.00 g/cm3  
40

Density When Liquid (at m.p.)
12.00 g/cm3  
31
10.07 g/cm3  
40

Tensile Strength
445.00 MPa  
9
65.00 MPa  
33

Viscosity
0.00  
28
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)  
25
0.00 (Pa)  
30

Elasticity properties
  
  

Shear Modulus
30.00 GPa  
27
25.00 GPa  
38

Bulk Modulus
110.00 GPa  
15
94.00 GPa  
17

Young's Modulus
78.00 GPa  
27
130.00 GPa  
16

Poisson Ratio
0.37  
7
0.34  
10

Other Mechanical Properties
Ductile, Malleable  
-  

Magnetic

Magnetic Characteristics
  
  

Specific Gravity
13.31  
30
10.07  
99+

Magnetic Ordering
Paramagnetic  
Paramagnetic  

Permeability
0.00 H/m  
9
0.00 H/m  
17

Susceptibility
0.00  
13
0.00  
24

Electrical Properties
  
  

Electrical Property
Conductor  
-  

Resistivity
331.00 nΩ·m  
14
5.20 nΩ·m  
99+

Electrical Conductivity
0.03 106/cm Ω  
99+
0.15 106/cm Ω  
13

Electron Affinity
0.00 kJ/mol  
99+
33.20 kJ/mol  
34

Thermal

Specific Heat
0.14 J/(kg K)  
38
0.12 J/(kg K)  
99+

Molar Heat Capacity
25.73 J/mol·K  
99+
27.20 J/mol·K  
24

Thermal Conductivity
23.00 W/m·K  
99+
12.00 W/m·K  
99+

Critical Temperature
2,500.00 K  
11
1,323.00 K  
99+

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

Enthalpy
  
  

Enthalpy of Vaporization
661.10 kJ/mol  
6
120.00 kJ/mol  
99+

Enthalpy of Fusion
25.10 kJ/mol  
8
14.20 kJ/mol  
28

Enthalpy of Atomization
703.00 kJ/mol  
5
301.00 kJ/mol  
99+

Standard Molar Entropy
43.60 J/mol.K  
99+
56.50 J/mol.K  
33

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