Symbol
Hf
  
Mg
  
Period Number
6
  
3
  
Block
d block
  
s block
  
Element Family
Transition Metal
  
Alkaline Earth
  
Space Group Name
P63/mmc
  
P63/mmc
  
Interesting Facts
- Hafnium metal is highly reactive, hence not found free in nature.
- Hafnium metal as predicated after Mendeleev finished his periodic table.
  
- Magnesium ions are present in every chlorophyll of every green plant .
- Controlling Magnesium fire by pouring water on it will result in explosions.
  
Sources
By-product Zirconium Refining
  
By Electrolysis Process, In Ocean, Mining
  
History
  
  
Who Discovered
Dirk Coster and George de Hevesy
  
Joseph Black
  
Discovery
In 1922
  
In 1755
  
Abundance
  
  
Abundance In Sun
~0.0000001 %
  
26
Abundance In Earth's Crust
Abundance In Humans
Not Available
  
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.
  
- Magnesium aluminum alloy improves the mechanical strength and welding characteristics and hence it is used in aeroplane and car manufacturing.
-
It is also used to remove sulfur from the molten iron and steel.
  
Industrial Uses
Ammunition Industry
  
Aerospace Industry, Ammunition Industry, Automobile Industry, Chemical Industry, Pharmaceutical Industry
  
Medical Uses
NA
  
NA
  
Other Uses
Alloys, In Nuclear Reactors, Nuclear Research, Research Purposes
  
Surgical Instruments Manufacturing
  
Biological Properties
  
  
Toxicity
Toxic
  
Non Toxic
  
Present in Human Body
No
  
Yes
  
In Blood
Not Available
  
37.80 Blood/mg dm-3
  
5
In Bone
Not Available
  
1,800.00 p.p.m.
  
4
Melting Point
2,150.00 °C
  
10
Boiling Point
1,107.00 °C
  
99+
Appearance
  
  
Physical State
Solid
  
Solid
  
Color
Gray
  
Gray
  
Luster
Metallic
  
NA
  
Hardness
  
  
Brinell Hardness
1,450.00 MPa
  
6
Vickers Hardness
1,520.00 MPa
  
5
Not Available
  
Speed of Sound
3,010.00 m/s
  
27
4,940.00 m/s
  
11
Optical Properties
  
  
Reflectivity
Not Available
  
Allotropes
No
  
No
  
α Allotropes
Not Available
  
Not Available
  
β Allotropes
Not Available
  
Not Available
  
γ Allotropes
Not Available
  
Not Available
  
Chemical Formula
Hf
  
Mg
  
Isotopes
  
  
Electronegativity
  
  
Pauling Electronegativity
Sanderson Electronegativity
Not Available
  
Allred Rochow Electronegativity
Mulliken-Jaffe Electronegativity
Not Available
  
Electropositivity
  
  
Pauling Electropositivity
Ionization Energies
  
  
1st Energy Level
658.50 kJ/mol
  
40
737.70 kJ/mol
  
24
2nd Energy Level
1,440.00 kJ/mol
  
99+
1,450.70 kJ/mol
  
99+
3rd Energy Level
2,250.00 kJ/mol
  
99+
7,732.70 kJ/mol
  
5
4th Energy Level
3,216.00 kJ/mol
  
99+
10,542.50 kJ/mol
  
4
5th Energy Level
Not Available
  
13,630.00 kJ/mol
  
3
6th Energy Level
Not Available
  
18,020.00 kJ/mol
  
3
7th Energy level
Not Available
  
21,711.00 kJ/mol
  
3
8th Energy Level
Not Available
  
25,661.00 kJ/mol
  
3
9th Energy Level
Not Available
  
31,653.00 kJ/mol
  
3
10th Energy Level
Not Available
  
35,458.00 kJ/mol
  
5
11th Energy Level
Not Available
  
169,988.00 kJ/mol
  
1
12th Energy Level
Not Available
  
189,368.00 kJ/mol
  
1
Electrochemical Equivalent
1.66 g/amp-hr
  
99+
0.45 g/amp-hr
  
99+
Other Chemical Properties
Anti Corrosion, Ionization, Radioactive Isotopes, Solubility
  
Corrosion, Highly Inflammable, Ionization, Solubility
  
Electron Configuration
[Xe] 4f14 5d2 6s2
  
[Ne] 3s2
  
Crystal Structure
Hexagonal Close Packed (HCP)
  
Hexagonal Close Packed (HCP)
  
Crystal Lattice
BCC-Crystal-Structure-.jpg#100
  
HCP-Crystal-Structure-of-Magnesium.jpg#100
  
Atom
  
  
Radius of an Atom
  
  
Atomic Volume
13.60 cm3/mol
  
38
13.97 cm3/mol
  
37
Adjacent Atomic Numbers
  
  
Valence Electron Potential
81.00 (-eV)
  
16
40.00 (-eV)
  
99+
Lattice Angles
π/2, π/2, 2 π/3
  
π/2, π/2, 2 π/3
  
Lattice C/A Ratio
Not Available
  
Density
  
  
Density At Room Temperature
13.31 g/cm
3
  
26
1.74 g/cm
3
  
99+
Density When Liquid (at m.p.)
12.00 g/cm3
  
12
1.58 g/cm3
  
99+
Tensile Strength
Not Available
  
Viscosity
Not Available
  
Not Available
  
Vapor Pressure
  
  
Vapor Pressure at 2000 K
Not Available
  
Elasticity properties
  
  
Other Mechanical Properties
Ductile, Malleable
  
NA
  
Magnetic Characteristics
  
  
Magnetic Ordering
Paramagnetic
  
Paramagnetic
  
Electrical Properties
  
  
Electrical Property
Conductor
  
Conductor
  
Resistivity
331.00 nΩ·m
  
14
43.90 nΩ·m
  
99+
Electrical Conductivity
0.03 10
6/cm Ω
  
39
0.23 10
6/cm Ω
  
7
Electron Affinity
0.00 kJ/mol
  
40
0.00 kJ/mol
  
40
Specific Heat
0.14 J/(kg K)
  
37
1.02 J/(kg K)
  
4
Molar Heat Capacity
25.73 J/mol·K
  
36
24.87 J/mol·K
  
99+
Thermal Conductivity
23.00 W/m·K
  
99+
156.00 W/m·K
  
8
Critical Temperature
Not Available
  
Not Available
  
Thermal Expansion
5.90 µm/(m·K)
  
99+
24.80 µm/(m·K)
  
15
Enthalpy
  
  
Enthalpy of Vaporization
661.10 kJ/mol
  
5
128.70 kJ/mol
  
99+
Enthalpy of Fusion
25.10 kJ/mol
  
8
8.95 kJ/mol
  
39
Enthalpy of Atomization
703.00 kJ/mol
  
5
148.50 kJ/mol
  
99+
Standard Molar Entropy
43.60 J/mol.K
  
34
32.70 J/mol.K
  
99+