Symbol
Hf
  
K
  
Period Number
6
  
4
  
Block
d block
  
s block
  
Element Family
Transition Metal
  
Alkali
  
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.
  
- In the list of most abundant element Potassium is ranked 7th.
- Potassium can easily be sliced (chopped) down using knife.
  
Sources
By-product Zirconium Refining
  
Found in Minerals, Mining
  
History
  
  
Who Discovered
Dirk Coster and George de Hevesy
  
Humphry Davy
  
Discovery
In 1922
  
In 1807
  
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.
  
- Potassium’s compounds are in high demand for their application in Fertilizer manufacturing.
- Potassium carbonate is used in glass manufacturing and Potassium carbonate in manufacturing detergent and body wash.
  
Industrial Uses
Ammunition Industry
  
Ammunition Industry, Chemical Industry
  
Medical Uses
NA
  
Pharmaceutical Industry
  
Other Uses
Alloys, In Nuclear Reactors, Nuclear Research, Research Purposes
  
NA
  
Biological Properties
  
  
Toxicity
Toxic
  
Toxic
  
Present in Human Body
No
  
Yes
  
In Blood
Not Available
  
1,620.00 Blood/mg dm-3
  
2
In Bone
Not Available
  
2,100.00 p.p.m.
  
3
Melting Point
2,150.00 °C
  
10
Appearance
  
  
Physical State
Solid
  
Solid
  
Color
Gray
  
Silvery 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
2,000.00 m/s
  
99+
Optical Properties
  
  
Allotropes
No
  
No
  
α Allotropes
Not Available
  
Not Available
  
β Allotropes
Not Available
  
Not Available
  
γ Allotropes
Not Available
  
Not Available
  
Chemical Formula
Hf
  
K
  
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
418.80 kJ/mol
  
99+
2nd Energy Level
1,440.00 kJ/mol
  
99+
3,052.00 kJ/mol
  
5
3rd Energy Level
2,250.00 kJ/mol
  
99+
4,420.00 kJ/mol
  
8
4th Energy Level
3,216.00 kJ/mol
  
99+
5,877.00 kJ/mol
  
9
5th Energy Level
Not Available
  
7,975.00 kJ/mol
  
8
6th Energy Level
Not Available
  
9,590.00 kJ/mol
  
13
7th Energy level
Not Available
  
11,343.00 kJ/mol
  
17
8th Energy Level
Not Available
  
14,944.00 kJ/mol
  
13
9th Energy Level
Not Available
  
16,963.70 kJ/mol
  
15
10th Energy Level
Not Available
  
48,610.00 kJ/mol
  
3
11th Energy Level
Not Available
  
54,490.00 kJ/mol
  
4
12th Energy Level
Not Available
  
60,730.00 kJ/mol
  
4
13th Energy Level
Not Available
  
68,950.00 kJ/mol
  
4
14th Energy Level
Not Available
  
75,900.00 kJ/mol
  
5
15th Energy Level
Not Available
  
83,080.00 kJ/mol
  
6
16th Energy Level
Not Available
  
93,400.00 kJ/mol
  
7
17th Energy Level
Not Available
  
99,710.00 kJ/mol
  
8
Electrochemical Equivalent
1.66 g/amp-hr
  
99+
1.46 g/amp-hr
  
99+
Other Chemical Properties
Anti Corrosion, Ionization, Radioactive Isotopes, Solubility
  
Chemical Stability, Flammability, Ionization, Solubility
  
Electron Configuration
[Xe] 4f14 5d2 6s2
  
[Ar] 4s1
  
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
45.46 cm3/mol
  
3
Adjacent Atomic Numbers
  
  
Valence Electron Potential
81.00 (-eV)
  
16
10.40 (-eV)
  
99+
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
0.86 g/cm3
  
99+
Density When Liquid (at m.p.)
12.00 g/cm3
  
12
0.83 g/cm3
  
99+
Tensile Strength
Not Available
  
Viscosity
Not Available
  
Not Available
  
Vapor Pressure
  
  
Vapor Pressure at 2000 K
Not Available
  
Elasticity properties
  
  
Poisson Ratio
Not Available
  
Other Mechanical Properties
Ductile, Malleable
  
NA
  
Magnetic Characteristics
  
  
Magnetic Ordering
Paramagnetic
  
Paramagnetic
  
Electrical Properties
  
  
Electrical Property
Conductor
  
Conductor
  
Resistivity
331.00 nΩ·m
  
14
Electrical Conductivity
0.03 106/cm Ω
  
39
0.14 106/cm Ω
  
14
Electron Affinity
0.00 kJ/mol
  
40
48.40 kJ/mol
  
22
Specific Heat
0.14 J/(kg K)
  
37
0.75 J/(kg K)
  
6
Molar Heat Capacity
25.73 J/mol·K
  
36
29.60 J/mol·K
  
6
Thermal Conductivity
23.00 W/m·K
  
99+
102.50 W/m·K
  
15
Critical Temperature
Not Available
  
Thermal Expansion
5.90 µm/(m·K)
  
99+
83.30 µm/(m·K)
  
3
Enthalpy
  
  
Enthalpy of Vaporization
661.10 kJ/mol
  
5
77.50 kJ/mol
  
99+
Enthalpy of Fusion
25.10 kJ/mol
  
8
2.32 kJ/mol
  
99+
Enthalpy of Atomization
703.00 kJ/mol
  
5
89.50 kJ/mol
  
99+
Standard Molar Entropy
43.60 J/mol.K
  
34
64.70 J/mol.K
  
18