Cadmium

Cadmium (Cd)

Soft bluish metal belonging to group 12 of the periodic table. Extremely toxic even in low concentrations. Chemically similar to zinc, but lends itself to more complex compounds. Discovered in 1817 by F. Stromeyer.
Atomic Number48
Atomic Weight112.414
Mass Number114
Group12
Period5
Blockd
Protons48 p+
Neutrons66 n0
Electrons48 e-
Cadmium-crystal bar.jpg Animated Bohr Model Enhanced Bohr Model Bohr Model Orbital Diagram

Properties

Atomic Radius
155 pm
Atomic Volume
Covalent Radius
136 pm
Metallic Radius
138 pm
Ionic Radius
78 pm
Crystal Radius
92 pm
Van der Waals radius
218.00000000000003 pm
Density
8.69 g/cm³
Boiling Point
1,038 K
Melting Point
594.1 K
Electrons per shell2, 8, 18, 18, 2
Electronegativity
1.69
Electrophilicity
Proton Affinity
Electron Affinity
Ionization Potential
8.993822 eV/particle
Heat of Vaporization
59.1 kJ/mol
Heat of Fusion
6.11 kJ/mol
Heat of Formation
111.8 kJ/mol
Molar Heat Capacity
26.02 J/(mol K)
Specific Heat Capacity
0.232 J/(g⋅K)
Thermal Conductivity
96.9 W/(m K)
Gas Basicity
Dipole Polarizability
46 a₀
C6 Dispersion Coefficient
Oxidation States1, 2
Color
Silver
Crystal StructureSimple Hexagonal (HEX)
Lattice Constant
2.98 Å
Bulk Modulus
Electrical Resistivity
Electron Configuration[Kr] 4d10 5s2
Magnetic Ordering
Magnetic Susceptibility
PhaseSolid
Poisson Ratio
Shear Modulus
Young's Modulus
Allotropes
Alternate Names
Adiabatic Index
Appearance
Electric Conductivity
Critical Pressure
Critical Temperature
Curie Point
Electrical
Hardness
Magnetic Susceptibility
Magnetic
Neel Point
Neutron Cross Section
Neutron Mass Absorption
Gas Phase
Quantum Numbers
Refractive Index
Space Group
Speed of Sound
Superconducting Point
Thermal Expansion
Valence Electrons
Classification
CategoryTransition metals, Transition metals
CAS GroupIIB
IUPAC GroupIIB
Glawe Number75
Mendeleev Number78
Pettifor Number75
Geochemical Class
Goldschmidt Classchalcophile
Radioactivity
RadioactiveNo
Decay Mode
Half-Life
Lifetime
Abundance
Abundance in Earth's crust
0.15 mg/kg
Abundance in Oceans
0.00011 mg/L
Abundance in Human Body
Abundance in Meteor
Abundance in Sun
Abundance in Universe2×10-7%

Isotopes of Cadmium

Stable Isotopes
106Cd 108Cd 110Cd 111Cd 112Cd 113Cd 114Cd 116Cd
Unstable Isotopes
95Cd 96Cd 97Cd 98Cd 99Cd 100Cd 101Cd 102Cd 103Cd 104Cd 105Cd 107Cd 109Cd 115Cd 117Cd 118Cd 119Cd 120Cd 121Cd 122Cd 123Cd 124Cd 125Cd 126Cd 127Cd 128Cd 129Cd 130Cd 131Cd 132Cd

History

Cadmium was discovered by German chemist Friedrich Stromeyer in 1817 as an impurity in zinc carbonate. Stromeyer noted that some impure samples of calamine (zinc carbonate) changed color when heated but pure calamine did not. Cadmium was independently discovered by German chemist Karl Hermann in 1818. From the Latin word cadmia, Greek kadmeia - the ancient name for calamine, zinc carbonate

DiscoverersFredrich Stromeyer
Discovery LocationGermany
Discovery Year1817
Name OriginGreek: kadmeia (ancient name for calamine (zinc oxide)).
Cadmium and its compounds are highly toxic
Cadmium is a soft metal which is easily cut with a knife

Uses

Cadmium is a key component in battery production. It is also is used in electroplating. Cadmium oxide is used in black and white television phosphors and in the blue and green phosphors for color television picture tubes. Cadmium is used as a barrier to control neutrons in nuclear fission. Used in nickel-cadmium batteries. Also in electroplating steel and in the manufacture of berings. Its compounds are found in paint pigments and a wide variety of intense colors. Boiling cadmium gives off a weird, yellow-colored vapor that is poisonous.

Sources

Obtained as a by product of zinc refining.