Symbol
Hf
  
Sc
  
Period Number
6
  
4
  
Block
d block
  
d block
  
Element Family
Transition Metal
  
Transition Metal
  
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.
  
- Scandium is known as one of the rare earth elements.
- Scandium metal found in rare minerals called Wolframite .
  
Sources
By-product Zirconium Refining
  
Found in Minerals, Mining, Ores of metals, Ores of Minerals
  
History
  
  
Who Discovered
Dirk Coster and George de Hevesy
  
Lars Fredrik Nilson
  
Discovery
In 1922
  
In 1879
  
Abundance
  
  
Abundance In Sun
~0.0000001 %
  
26
~0.000004 %
  
16
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.
  
- Uses of Scandium are limited to research purpose only. However, it has very low density and higher melting point.
-
Its compounds like scandium iodide is used in mercury vapor lamps to produce very bright white light.
  
Industrial Uses
Ammunition 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
  
0.01 Blood/mg dm-3
  
22
In Bone
Not Available
  
0.00 p.p.m.
  
34
Melting Point
2,150.00 °C
  
10
1,539.00 °C
  
24
Boiling Point
2,832.00 °C
  
35
Appearance
  
  
Physical State
Solid
  
Solid
  
Color
Gray
  
Silvery White
  
Luster
Metallic
  
Lustrous
  
Hardness
  
  
Mohs Hardness
Not Available
  
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
Not Available
  
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
  
Sc
  
Isotopes
  
  
Electronegativity
  
  
Pauling Electronegativity
Sanderson Electronegativity
Not Available
  
Allred Rochow Electronegativity
Electropositivity
  
  
Pauling Electropositivity
Ionization Energies
  
  
1st Energy Level
658.50 kJ/mol
  
40
633.10 kJ/mol
  
99+
2nd Energy Level
1,440.00 kJ/mol
  
99+
1,235.00 kJ/mol
  
99+
3rd Energy Level
2,250.00 kJ/mol
  
99+
2,388.60 kJ/mol
  
99+
4th Energy Level
3,216.00 kJ/mol
  
99+
7,090.60 kJ/mol
  
6
5th Energy Level
Not Available
  
8,843.00 kJ/mol
  
6
6th Energy Level
Not Available
  
10,679.00 kJ/mol
  
7
7th Energy level
Not Available
  
13,310.00 kJ/mol
  
8
8th Energy Level
Not Available
  
15,250.00 kJ/mol
  
11
9th Energy Level
Not Available
  
17,370.00 kJ/mol
  
14
10th Energy Level
Not Available
  
21,726.00 kJ/mol
  
13
11th Energy Level
Not Available
  
24,102.00 kJ/mol
  
16
12th Energy Level
Not Available
  
66,320.00 kJ/mol
  
2
13th Energy Level
Not Available
  
73,010.00 kJ/mol
  
2
14th Energy Level
Not Available
  
80,160.00 kJ/mol
  
3
15th Energy Level
Not Available
  
89,490.00 kJ/mol
  
4
16th Energy Level
Not Available
  
97,400.00 kJ/mol
  
5
17th Energy Level
Not Available
  
105,600.00 kJ/mol
  
6
18th Energy Level
Not Available
  
117,000.00 kJ/mol
  
7
19th Energy Level
Not Available
  
124,270.00 kJ/mol
  
8
Electrochemical Equivalent
1.66 g/amp-hr
  
99+
0.56 g/amp-hr
  
99+
Other Chemical Properties
Anti Corrosion, Ionization, Radioactive Isotopes, Solubility
  
Corrosion, Flammable, Ionization, Radioactive Isotopes, Solubility
  
Electron Configuration
[Xe] 4f14 5d2 6s2
  
[Ar] 3d1 4s2
  
Crystal Structure
Hexagonal Close Packed (HCP)
  
Hexagonal Close Packed (HCP)
  
Crystal Lattice
BCC-Crystal-Structure-.jpg#100
  
HCP-Crystal-Structure-of-Scandium.jpg#100
  
Atom
  
  
Radius of an Atom
  
  
Atomic Volume
13.60 cm3/mol
  
38
15.00 cm3/mol
  
34
Adjacent Atomic Numbers
  
  
Valence Electron Potential
81.00 (-eV)
  
16
58.00 (-eV)
  
24
Lattice Angles
π/2, π/2, 2 π/3
  
π/2, π/2, 2 π/3
  
Density
  
  
Density At Room Temperature
13.31 g/cm3
  
26
2.99 g/cm3
  
99+
Density When Liquid (at m.p.)
12.00 g/cm3
  
12
2.80 g/cm3
  
99+
Tensile Strength
Not Available
  
Viscosity
Not Available
  
Not Available
  
Vapor Pressure
  
  
Vapor Pressure at 1000 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
562.00 nΩ·m
  
10
Electrical Conductivity
0.03 106/cm Ω
  
39
0.02 106/cm Ω
  
99+
Electron Affinity
0.00 kJ/mol
  
40
18.10 kJ/mol
  
33
Specific Heat
0.14 J/(kg K)
  
37
0.60 J/(kg K)
  
8
Molar Heat Capacity
25.73 J/mol·K
  
36
25.52 J/mol·K
  
37
Thermal Conductivity
23.00 W/m·K
  
99+
15.80 W/m·K
  
99+
Critical Temperature
Not Available
  
Not Available
  
Thermal Expansion
5.90 µm/(m·K)
  
99+
10.20 µm/(m·K)
  
39
Enthalpy
  
  
Enthalpy of Vaporization
661.10 kJ/mol
  
5
314.20 kJ/mol
  
28
Enthalpy of Fusion
25.10 kJ/mol
  
8
14.10 kJ/mol
  
25
Enthalpy of Atomization
703.00 kJ/mol
  
5
343.00 kJ/mol
  
28
Standard Molar Entropy
43.60 J/mol.K
  
34
34.60 J/mol.K
  
99+