Symbol
Hf
  
W
  
Period Number
6
  
6
  
Block
d block
  
d block
  
Element Family
Transition Metal
  
Transition Metal
  
Space Group Name
P63/mmc
  
Im_ 3m
  
Interesting Facts
- Hafnium metal is highly reactive, hence not found free in nature.
- Hafnium metal as predicated after Mendeleev finished his periodic table.
  
- Tungsten element has the second highest melting point.
- Pure tungsten can easily cut down with the help of hacksaw.
  
Sources
By-product Zirconium Refining
  
Earth's crust, Found in Minerals, Mining, Ores of Minerals
  
History
  
  
Who Discovered
Dirk Coster and George de Hevesy
  
Not Available
  
Discovery
In 1922
  
In 1781
  
Abundance
  
  
Abundance In Sun
~0.0000001 %
  
26
~0.0000004 %
  
23
Abundance In Earth's Crust
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.
  
- Tungsten and its alloys are used in high-temperature applications like welding electrodes, high-temperature furnace, etc.
- Tungsten carbide is very hard and used in metal working, mining and petroleum industry.
  
Industrial Uses
Ammunition Industry
  
Aerospace Industry, Automobile Industry, Electrical Industry, Electronic Industry
  
Medical Uses
NA
  
NA
  
Other Uses
Alloys, In Nuclear Reactors, Nuclear Research, Research Purposes
  
Alloys
  
Biological Properties
  
  
Toxicity
Toxic
  
Non Toxic
  
Present in Human Body
No
  
Yes
  
In Blood
Not Available
  
0.00 Blood/mg dm-3
  
31
In Bone
Not Available
  
0.00 p.p.m.
  
35
Melting Point
2,150.00 °C
  
10
Appearance
  
  
Physical State
Solid
  
Solid
  
Color
Gray
  
Grayish White
  
Luster
Metallic
  
Lustrous
  
Hardness
  
  
Brinell Hardness
1,450.00 MPa
  
6
2,000.00 MPa
  
4
Vickers Hardness
1,520.00 MPa
  
5
3,430.00 MPa
  
1
Speed of Sound
3,010.00 m/s
  
27
4,620.00 m/s
  
16
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
  
W
  
Isotopes
  
  
Electronegativity
  
  
Pauling Electronegativity
Sanderson Electronegativity
Not Available
  
Allred Rochow Electronegativity
Electropositivity
  
  
Pauling Electropositivity
Ionization Energies
  
  
1st Energy Level
658.50 kJ/mol
  
40
770.00 kJ/mol
  
16
2nd Energy Level
1,440.00 kJ/mol
  
99+
1,700.00 kJ/mol
  
29
3rd Energy Level
2,250.00 kJ/mol
  
99+
Not Available
  
4th Energy Level
3,216.00 kJ/mol
  
99+
Not Available
  
Electrochemical Equivalent
1.66 g/amp-hr
  
99+
1.14 g/amp-hr
  
99+
Other Chemical Properties
Anti Corrosion, Ionization, Radioactive Isotopes, Solubility
  
Ionization, Radioactive Isotopes, Solubility
  
Electron Configuration
[Xe] 4f14 5d2 6s2
  
[Xe] 4f14 5d4 6s2
  
Crystal Structure
Hexagonal Close Packed (HCP)
  
Body Centered Cubic (BCC)
  
Crystal Lattice
BCC-Crystal-Structure-.jpg#100
  
BCC-Crystal-Structure-.jpg#100
  
Atom
  
  
Radius of an Atom
  
  
Atomic Volume
13.60 cm3/mol
  
38
9.53 cm3/mol
  
99+
Adjacent Atomic Numbers
  
  
Valence Electron Potential
81.00 (-eV)
  
16
140.00 (-eV)
  
5
Lattice Angles
π/2, π/2, 2 π/3
  
π/2, π/2, π/2
  
Lattice C/A Ratio
Not Available
  
Density
  
  
Density At Room Temperature
13.31 g/cm3
  
26
19.25 g/cm3
  
16
Density When Liquid (at m.p.)
12.00 g/cm3
  
12
Viscosity
Not Available
  
Not Available
  
Vapor Pressure
  
  
Elasticity properties
  
  
Other Mechanical Properties
Ductile, Malleable
  
Ductile, Malleable
  
Magnetic Characteristics
  
  
Magnetic Ordering
Paramagnetic
  
Paramagnetic
  
Electrical Properties
  
  
Electrical Property
Conductor
  
Superconductor
  
Resistivity
331.00 nΩ·m
  
14
52.80 nΩ·m
  
99+
Electrical Conductivity
0.03 106/cm Ω
  
39
0.19 106/cm Ω
  
10
Electron Affinity
0.00 kJ/mol
  
40
78.60 kJ/mol
  
13
Specific Heat
0.14 J/(kg K)
  
37
0.13 J/(kg K)
  
39
Molar Heat Capacity
25.73 J/mol·K
  
36
24.27 J/mol·K
  
99+
Thermal Conductivity
23.00 W/m·K
  
99+
173.00 W/m·K
  
7
Critical Temperature
Not Available
  
Not Available
  
Thermal Expansion
5.90 µm/(m·K)
  
99+
4.50 µm/(m·K)
  
99+
Enthalpy
  
  
Enthalpy of Vaporization
661.10 kJ/mol
  
5
799.10 kJ/mol
  
1
Enthalpy of Fusion
25.10 kJ/mol
  
8
35.23 kJ/mol
  
1
Enthalpy of Atomization
703.00 kJ/mol
  
5
837.00 kJ/mol
  
1
Standard Molar Entropy
43.60 J/mol.K
  
34
32.60 J/mol.K
  
99+