Symbol
Cd
  
Hf
  
Period Number
5
  
6
  
Block
d block
  
d block
  
Element Family
Transition Metal
  
Transition Metal
  
Space Group Name
P63/mmc
  
P63/mmc
  
Interesting Facts
- Naturally occurring minor elements include Cadmium.
- Cadmium is released into atmosphere to control volcanic eruption and forest fires.
- It is used for electroplating of Steel for corrosion resistance.
- It can absorb neutrons and used in nuclear reactor to control atomic fission.
  
- Hafnium metal is highly reactive, hence not found free in nature.
- Hafnium metal as predicated after Mendeleev finished his periodic table.
  
Sources
Found As a By-product, Found in Minerals, Mining
  
By-product Zirconium Refining
  
History
  
  
Who Discovered
Karl Samuel Leberecht Hermann and Friedrich Stromeyer
  
Dirk Coster and George de Hevesy
  
Discovery
In 1817
  
In 1922
  
Abundance
  
  
Abundance In Sun
~0.0000006 %
  
21
~0.0000001 %
  
26
Abundance In Earth's Crust
Abundance In Humans
Not Available
  
Uses & Benefits
- It has very limited uses as it is a toxic metal and it can cause birth defects, cancer, etc.
-
Almost 80% of Cadmium metal is used in Nickel cadmium Batteries and now it is getting replaced with nickel hydride.
  
- 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
Aerospace Industry, Ammunition Industry, Chemical Industry, Electrical Industry, Electronic Industry
  
Ammunition Industry
  
Medical Uses
NA
  
NA
  
Other Uses
Alloys
  
Alloys, In Nuclear Reactors, Nuclear Research, Research Purposes
  
Biological Properties
  
  
Toxicity
Toxic
  
Toxic
  
Present in Human Body
Yes
  
No
  
In Blood
0.01 Blood/mg dm-3
  
24
Not Available
  
In Bone
1.80 p.p.m.
  
15
Not Available
  
Melting Point
2,150.00 °C
  
10
Appearance
  
  
Physical State
Solid
  
Solid
  
Color
Silvery Bluish-Gray
  
Gray
  
Luster
Metallic
  
Metallic
  
Hardness
  
  
Brinell Hardness
1,450.00 MPa
  
6
Vickers Hardness
Not Available
  
1,520.00 MPa
  
5
Speed of Sound
2,310.00 m/s
  
39
3,010.00 m/s
  
27
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
Cd
  
Hf
  
Isotopes
  
  
Electronegativity
  
  
Pauling Electronegativity
Sanderson Electronegativity
Not Available
  
Allred Rochow Electronegativity
Mulliken-Jaffe Electronegativity
Not Available
  
Electropositivity
  
  
Pauling Electropositivity
Ionization Energies
  
  
1st Energy Level
867.80 kJ/mol
  
11
658.50 kJ/mol
  
40
2nd Energy Level
1,631.40 kJ/mol
  
32
1,440.00 kJ/mol
  
99+
3rd Energy Level
3,616.00 kJ/mol
  
13
2,250.00 kJ/mol
  
99+
4th Energy Level
Not Available
  
3,216.00 kJ/mol
  
99+
Electrochemical Equivalent
2.10 g/amp-hr
  
27
1.66 g/amp-hr
  
99+
Other Chemical Properties
Chemical Stability, Anti Corrosion, Ionization, Radioactive Isotopes, Solubility
  
Anti Corrosion, Ionization, Radioactive Isotopes, Solubility
  
Electron Configuration
[Kr] 4d10 5s2
  
[Xe] 4f14 5d2 6s2
  
Crystal Structure
Hexagonal Close Packed (HCP)
  
Hexagonal Close Packed (HCP)
  
Crystal Lattice
HCP-Crystal-Structure-of-Cadmium.jpg#100
  
BCC-Crystal-Structure-.jpg#100
  
Atom
  
  
Radius of an Atom
  
  
Atomic Weight
112.41 amu
  
99+
Atomic Volume
13.10 cm3/mol
  
39
13.60 cm3/mol
  
38
Adjacent Atomic Numbers
  
  
Valence Electron Potential
30.00 (-eV)
  
99+
81.00 (-eV)
  
16
Lattice Angles
π/2, π/2, 2 π/3
  
π/2, π/2, 2 π/3
  
Density
  
  
Density At Room Temperature
8.65 g/cm3
  
99+
13.31 g/cm3
  
26
Density When Liquid (at m.p.)
12.00 g/cm3
  
12
Viscosity
Not Available
  
Not Available
  
Vapor Pressure
  
  
Vapor Pressure at 2000 K
Not Available
  
Elasticity properties
  
  
Other Mechanical Properties
Ductile, Malleable
  
Ductile, Malleable
  
Magnetic Characteristics
  
  
Magnetic Ordering
Diamagnetic
  
Paramagnetic
  
Electrical Properties
  
  
Electrical Property
Semiconductor
  
Conductor
  
Resistivity
331.00 nΩ·m
  
14
Electrical Conductivity
0.14 106/cm Ω
  
15
0.03 106/cm Ω
  
39
Electron Affinity
0.00 kJ/mol
  
40
0.00 kJ/mol
  
40
Specific Heat
0.23 J/(kg K)
  
26
0.14 J/(kg K)
  
37
Molar Heat Capacity
26.02 J/mol·K
  
32
25.73 J/mol·K
  
36
Thermal Conductivity
96.60 W/m·K
  
16
23.00 W/m·K
  
99+
Critical Temperature
Not Available
  
Not Available
  
Thermal Expansion
30.80 µm/(m·K)
  
10
5.90 µm/(m·K)
  
99+
Enthalpy
  
  
Enthalpy of Vaporization
100.00 kJ/mol
  
99+
661.10 kJ/mol
  
5
Enthalpy of Fusion
6.19 kJ/mol
  
99+
25.10 kJ/mol
  
8
Enthalpy of Atomization
113.00 kJ/mol
  
99+
703.00 kJ/mol
  
5
Standard Molar Entropy
51.80 J/mol.K
  
27
43.60 J/mol.K
  
34