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Actinium Hafnium Comparison


Hafnium Actinium comparison


Periodic Table

Symbol
Ac   
Hf   

Group Number
Not Available   
4   
14

Period Number
7   
6   

Block
f block   
d block   

Element Family
Actinide   
Transition Metal   

CAS Number
7440348   
99+
7440586   
30

Space Group Name
Fm_ 3m   
P63/mmc   

Space Group Number
225.00   
2
194.00   
5

Facts

Interesting Facts
Not Available   
  • Hafnium metal is highly reactive, hence not found free in nature.
  • Hafnium metal as predicated after Mendeleev finished his periodic table.
  

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

History
  
  

Who Discovered
Friedrich Oskar Giesel   
Dirk Coster and George de Hevesy   

Discovery
In 1902   
In 1922   

Abundance
  
  

Abundance In Universe
Not Available   
7 * 10-8 %   
25

Abundance In Sun
~-9999 %   
~0.0000001 %   
26

Abundance In Meteorites
Not Available   
0.00 %   
37

Abundance In Earth's Crust
Not Available   
0.00 %   
31

Abundance In Oceans
Not Available   
0.00 %   
27

Uses

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

Industrial Uses
NA   
Ammunition Industry   

Medical Uses
NA   
NA   

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

Biological Properties
  
  

Toxicity
Toxic   
Toxic   

Present in Human Body
No   
No   

In Blood
0.00 Blood/mg dm-3   
37
Not Available   

In Bone
0.00 p.p.m.   
36
Not Available   

Physical Properties

Melting Point
1,227.00 °C   
38
2,150.00 °C   
10

Boiling Point
3,200.00 °C   
26
5,400.00 °C   
5

Appearance
  
  

Physical State
Solid   
Solid   

Color
Silvery White   
Gray   

Luster
NA   
Metallic   

Hardness
  
  

Mohs Hardness
Not Available   
5.50   
7

Brinell Hardness
Not Available   
1,450.00 MPa   
6

Vickers Hardness
Not Available   
1,520.00 MPa   
5

Speed of Sound
Not Available   
3,010.00 m/s   
27

Optical Properties
  
  

Allotropes
No   
No   

α Allotropes
Not Available   
Not Available   

β Allotropes
Not Available   
Not Available   

γ Allotropes
Not Available   
Not Available   

Chemical Properties

Chemical Formula
Ac   
Hf   

Isotopes
  
  

Known Isotopes
29   
10
32   
7

Electronegativity
  
  

Pauling Electronegativity
1.10   
99+
1.30   
32

Allred Rochow Electronegativity
1.00   
36
1.23   
25

Allen Electronegativity
Not Available   
1.16   
37

Electropositivity
  
  

Pauling Electropositivity
2.90   
10
2.70   
22

Ionization Energies
  
  

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

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

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

4th Energy Level
4,700.00 kJ/mol   
23
3,216.00 kJ/mol   
99+

Electrochemical Equivalent
2.82 g/amp-hr   
18
1.66 g/amp-hr   
99+

Electron Work Function
Not Available   
3.90 eV   
27

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

Atomic Properties

Atomic Number
89   
29
72   
99+

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

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

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

Atom
  
  

Number of Protons
89   
29
72   
99+

Number of Neutrons
138   
16
106   
29

Number of Electrons
89   
29
72   
99+

Radius of an Atom
  
  

Atomic Radius
195.00 pm   
7
159.00 pm   
28

Covalent Radius
Not Available   
175.00 pm   
23

Van der Waals Radius
Not Available   
200.00 pm   
28

Atomic Weight
227.00 amu   
25
178.49 amu   
39

Atomic Volume
22.54 cm3/mol   
11
13.60 cm3/mol   
38

Adjacent Atomic Numbers
  
  

Previous Element
Radium
  
Lutetium
  

Next Element
Thorium
  
Tantalum
  

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

Lattice Constant
567.00 pm   
8
319.64 pm   
99+

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

Lattice C/A Ratio
Not Available   
1.58   
12

Mechanical Properties

Density
  
  

Density At Room Temperature
10.00 g/cm3   
37
13.31 g/cm3   
26

Density When Liquid (at m.p.)
Not Available   
12.00 g/cm3   
12

Tensile Strength
Not Available   
445.00 MPa   
8

Viscosity
Not Available   
Not Available   

Vapor Pressure
  
  

Vapor Pressure at 2000 K
Not Available   
0.00 (Pa)   
24

Elasticity properties
  
  

Shear Modulus
Not Available   
30.00 GPa   
23

Bulk Modulus
Not Available   
110.00 GPa   
15

Young's Modulus
Not Available   
78.00 GPa   
25

Poisson Ratio
Not Available   
0.37   
7

Other Mechanical Properties
NA   
Ductile, Malleable   

Magnetic Properties

Magnetic Characteristics
  
  

Specific Gravity
10.07   
28
13.31   
18

Magnetic Ordering
Paramagnetic   
Paramagnetic   

Electrical Properties
  
  

Electrical Property
Unknown   
Conductor   

Resistivity
Not Available   
331.00 nΩ·m   
14

Electrical Conductivity
Not Available   
0.03 106/cm Ω   
39

Electron Affinity
Not Available   
0.00 kJ/mol   
40

Thermal Properties

Specific Heat
0.12 J/(kg K)   
40
0.14 J/(kg K)   
37

Molar Heat Capacity
27.20 J/mol·K   
18
25.73 J/mol·K   
36

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

Critical Temperature
Not Available   
Not Available   

Thermal Expansion
Not Available   
5.90 µm/(m·K)   
99+

Enthalpy
  
  

Enthalpy of Vaporization
Not Available   
661.10 kJ/mol   
5

Enthalpy of Fusion
Not Available   
25.10 kJ/mol   
8

Enthalpy of Atomization
301.00 kJ/mol   
36
703.00 kJ/mol   
5

Standard Molar Entropy
56.50 J/mol.K   
25
43.60 J/mol.K   
34

Summary >>
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