Group 12 element
Encyclopedia
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| 4 Period 4 element A period 4 element is one of the chemical elements in the fourth row of the periodic table of the elements. The periodic table is laid out in rows to illustrate recurring trends in the chemical behaviour of the elements as their atomic number increases: a new row is begun when chemical behaviour... |
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| 5 Period 5 element A period 5 element is one of the chemical elements in the fifth row of the periodic table of the elements. The periodic table is laid out in rows to illustrate recurring trends in the chemical behaviour of the elements as their atomic number increases: a new row is begun when chemical behaviour... |
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| 6 Period 6 element A period 6 element is one of the chemical elements in the sixth row of the periodic table of the elements, including the lanthanides... |
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| 7 Period 7 element A period 7 element is one of the chemical elements in the seventh row of the periodic table of the chemical elements. The periodic table is laid out in rows to illustrate recurring trends in the chemical behaviour of the elements as their atomic number increases: a new row is begun when chemical... |
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A group 12 element is one of the elements
Chemical element
A chemical element is a pure chemical substance consisting of one type of atom distinguished by its atomic number, which is the number of protons in its nucleus. Familiar examples of elements include carbon, oxygen, aluminum, iron, copper, gold, mercury, and lead.As of November 2011, 118 elements...
in group 12
Periodic table group
In chemistry, a group is a vertical column in the periodic table of the chemical elements. There are 18 groups in the standard periodic table, including the d-block elements, but excluding the f-block elements....
(IUPAC style) in the periodic table
Periodic table
The periodic table of the chemical elements is a tabular display of the 118 known chemical elements organized by selected properties of their atomic structures. Elements are presented by increasing atomic number, the number of protons in an atom's atomic nucleus...
. This includes zinc
Zinc
Zinc , or spelter , is a metallic chemical element; it has the symbol Zn and atomic number 30. It is the first element in group 12 of the periodic table. Zinc is, in some respects, chemically similar to magnesium, because its ion is of similar size and its only common oxidation state is +2...
(Zn), cadmium
Cadmium
Cadmium is a chemical element with the symbol Cd and atomic number 48. This soft, bluish-white metal is chemically similar to the two other stable metals in group 12, zinc and mercury. Similar to zinc, it prefers oxidation state +2 in most of its compounds and similar to mercury it shows a low...
(Cd) and mercury
Mercury (element)
Mercury is a chemical element with the symbol Hg and atomic number 80. It is also known as quicksilver or hydrargyrum...
(Hg). The further inclusion of copernicium (Cn) in group 12 is supported by recent experiments on individual Cn atoms. Although this group lies in the d-block
D-block
The d-block is the portion of the periodic table that contains the element groups 3-12. These groups correspond to the filling of the atomic d-orbital subshell, with electron configurations ranging from s2d1 to s2d10...
of the periodic table it is not considered to be a part of the transition metals as the elements in this group have a filled d-subshell.
The three Group 12 elements that occur naturally are zinc
Zinc
Zinc , or spelter , is a metallic chemical element; it has the symbol Zn and atomic number 30. It is the first element in group 12 of the periodic table. Zinc is, in some respects, chemically similar to magnesium, because its ion is of similar size and its only common oxidation state is +2...
, cadmium
Cadmium
Cadmium is a chemical element with the symbol Cd and atomic number 48. This soft, bluish-white metal is chemically similar to the two other stable metals in group 12, zinc and mercury. Similar to zinc, it prefers oxidation state +2 in most of its compounds and similar to mercury it shows a low...
and mercury
Mercury (element)
Mercury is a chemical element with the symbol Hg and atomic number 80. It is also known as quicksilver or hydrargyrum...
. The first two members of the group share similar properties; as they are solid metals. Mercury
Mercury (element)
Mercury is a chemical element with the symbol Hg and atomic number 80. It is also known as quicksilver or hydrargyrum...
is the only metal that is a liquid at room temperature. As copernicium does not occur in a natural, stable form in nature, it has to be synthesized in the laboratory.
Chemistry
All elements in this group are metalMetal
A metal , is an element, compound, or alloy that is a good conductor of both electricity and heat. Metals are usually malleable and shiny, that is they reflect most of incident light...
s. The similarity of the metallic radii of cadmium and mercury is a knock-on effect of the lanthanide contraction
Lanthanide contraction
Lanthanide contraction is a term used in chemistry to describe the decrease in ionic radii of the elements in the lanthanide series from atomic number 58, Cerium to 71, Lutetium, which results in smaller than otherwise expected ionic radii for the subsequent elements starting with 72, Hafnium...
. So, the trend in this group is unlike the trend in group 2, the alkaline earths, where metallic radius increases smoothly from top to bottom of the group. All three metals have relatively low melting and boiling points, indicating that the metallic bond
Metallic bond
Metallic bonding is the electrostatic attractive forces between the delocalized electrons, called conduction electrons, gathered in an "electron sea", and the positively charged metal ions...
is relatively weak, with relatively little overlap between the valence band
Valence band
In solids, the valence band is the highest range of electron energies in which electrons are normally present at absolute zero temperature....
and the conduction band
Conduction band
In the solid-state physics field of semiconductors and insulators, the conduction band is the range of electron energies, higher than that of the valence band, sufficient to free an electron from binding with its individual atom and allow it to move freely within the atomic lattice of the material...
. Thus, zinc is close to the boundary between metallic and metalloid
Metalloid
Metalloid is a term used in chemistry when classifying the chemical elements. On the basis of their general physical and chemical properties, each element can usually be classified as a metal or a nonmetal. However, some elements with intermediate or mixed properties can be harder to characterize...
elements, which is usually placed between gallium
Gallium
Gallium is a chemical element that has the symbol Ga and atomic number 31. Elemental gallium does not occur in nature, but as the gallium salt in trace amounts in bauxite and zinc ores. A soft silvery metallic poor metal, elemental gallium is a brittle solid at low temperatures. As it liquefies...
and germanium
Germanium
Germanium is a chemical element with the symbol Ge and atomic number 32. It is a lustrous, hard, grayish-white metalloid in the carbon group, chemically similar to its group neighbors tin and silicon. The isolated element is a semiconductor, with an appearance most similar to elemental silicon....
, though gallium participates in semi-conductors such as gallium arsenide.
Zinc and cadmium are the electropositive elements in the group while mercury is not. As a result, zinc metal and cadmium are good reducing agents. The elements of group group 12 have an oxidation state of +2 in which the ions have the rather stable d10 electronic configuration, with a full sub-shell
Electron shell
An electron shell may be thought of as an orbit followed by electrons around an atom's nucleus. The closest shell to the nucleus is called the "1 shell" , followed by the "2 shell" , then the "3 shell" , and so on further and further from the nucleus. The shell letters K,L,M,.....
. However, mercury can easily be reduced to the +1 oxidation state; usually, as in the ion Hg22+, two mercury(I) ions come together to form a metal-metal bond and a diamagnetic species. Cadmium can also form species such as [Cd2Cl6]4− in which the metal's oxidation state is +1. Just as with mercury, the formation of a metal-metal bond results in a diamagnetic compound in which there are no unpaired electrons; thus, making the species very reactive. Zinc(I) is known only in the gas phase, in such compounds as linear Zn2Cl2, analogous to calomel.
All three metal ions form many tetrahedral
Tetrahedral molecular geometry
In a tetrahedral molecular geometry a central atom is located at the center with four substituents that are located at the corners of a tetrahedron. The bond angles are cos−1 ≈ 109.5° when all four substituents are the same, as in CH4. This molecular geometry is common throughout the first...
species, such as MCl42−. When a divalent ion of these elements forms a tetrahedral complex
Complex (chemistry)
In chemistry, a coordination complex or metal complex, is an atom or ion , bonded to a surrounding array of molecules or anions, that are in turn known as ligands or complexing agents...
, it obeys the octet rule
Octet rule
The octet rule is a chemical rule of thumb that states that atoms of low The octet rule is a chemical rule of thumb that states that atoms of low The octet rule is a chemical rule of thumb that states that atoms of low (The octet rule is a chemical rule of thumb that states that atoms of low (...
. Both zinc and cadmium can also form octahedral complexes such as the aqua ions
Metal ions in aqueous solution
A metal ion in aqueous solution is a cation, dissolved in water, of chemical formula [Mn]z+. The solvation number, n, determined by a variety of experimental methods is 4 for Li+ and Be2+ and 6 for elements in rows 3 and 4 of the periodic table. Lanthanide and actinide aqua ions have solvation...
[M(H2O)6]2+ which are present in aqueous solutions of salts of these metals. Covalent character is achieved by using the 4d or 5d orbitals, respectively, forming sp3d2 hybrid orbitals
Orbital hybridisation
In chemistry, hybridisation is the concept of mixing atomic orbitals to form new hybrid orbitals suitable for the qualitative description of atomic bonding properties. Hybridised orbitals are very useful in the explanation of the shape of molecular orbitals for molecules. It is an integral part...
. Mercury, however, rarely exceeds a coordination number
Coordination number
In chemistry and crystallography, the coordination number of a central atom in a molecule or crystal is the number of its nearest neighbours. This number is determined somewhat differently for molecules and for crystals....
of four; when it does so the 5f orbitals must be involved. Coordination numbers of 2, 3, 5, 7 and 8 are also known.
The elements in group 12 are usually considered to be d-block
D-block
The d-block is the portion of the periodic table that contains the element groups 3-12. These groups correspond to the filling of the atomic d-orbital subshell, with electron configurations ranging from s2d1 to s2d10...
elements, but not transition elements as the d-shell is full. Some authors classify these elements as main-group elements because the valence electrons are in ns2 orbitals. Nevertheless zinc shares many characteristics with the neighboring transition metal, copper. For instance, zinc complexes merit inclusion in the Irving-Williams series
Irving-Williams series
The Irving-Williams Series refers to the relative stabilities of complexes formed by a metal ion. For high-spin complexes of the divalent ions of first-row transition metals, the stability constant for the formation of a complex follows the orderThe Irving-Williams Series refers to the relative...
as zinc forms many complexes with the same stoichiometry
Stoichiometry
Stoichiometry is a branch of chemistry that deals with the relative quantities of reactants and products in chemical reactions. In a balanced chemical reaction, the relations among quantities of reactants and products typically form a ratio of whole numbers...
as complexes of copper(II), albeit with smaller stability constants
Stability constants of complexes
A stability constant is an equilibrium constant for the formation of a complex in solution. It is a measure of the strength of the interaction between the reagents that come together to form the complex...
. There is little similarity between cadmium and silver as compounds of silver(II) are rare and those that do exist are very strong oxidizing agents. Likewise the common oxidation state for gold is +3, which precludes there being much common chemistry between mercury and gold, though there are similarities between mercury(I) and gold(I) such as the formation of linear dicyano complexes, [M(CN)2]−.
Physical
The table below is a summary of the key physical properties of the group 12 elements.| Zinc Zinc Zinc , or spelter , is a metallic chemical element; it has the symbol Zn and atomic number 30. It is the first element in group 12 of the periodic table. Zinc is, in some respects, chemically similar to magnesium, because its ion is of similar size and its only common oxidation state is +2... | Cadmium Cadmium Cadmium is a chemical element with the symbol Cd and atomic number 48. This soft, bluish-white metal is chemically similar to the two other stable metals in group 12, zinc and mercury. Similar to zinc, it prefers oxidation state +2 in most of its compounds and similar to mercury it shows a low... | Mercury Mercury (element) Mercury is a chemical element with the symbol Hg and atomic number 80. It is also known as quicksilver or hydrargyrum... | Copernicium | |
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| Electronic configuration | ||||
| Melting point Melting point The melting point of a solid is the temperature at which it changes state from solid to liquid. At the melting point the solid and liquid phase exist in equilibrium. The melting point of a substance depends on pressure and is usually specified at standard atmospheric pressure... /°C |
419.5 | 320.8 | −38.9 | ? |
| Boiling point Boiling point The boiling point of an element or a substance is the temperature at which the vapor pressure of the liquid equals the environmental pressure surrounding the liquid.... /°C |
907 | 765 | 357 | ? |
| Atomic Radius | 134 pm | 151 pm | 151 pm | ? |
| Density Density The mass density or density of a material is defined as its mass per unit volume. The symbol most often used for density is ρ . In some cases , density is also defined as its weight per unit volume; although, this quantity is more properly called specific weight... |
7.14 g·cm−3 | 8.65 g·cm−3 | 13.534 g·cm−3 | ? |
| Electronegativity Electronegativity Electronegativity, symbol χ , is a chemical property that describes the tendency of an atom or a functional group to attract electrons towards itself. An atom's electronegativity is affected by both its atomic number and the distance that its valence electrons reside from the charged nucleus... |
1.6 | 1.7 | 1.9 | ? |
History
The elements of group 12 have been found throughout historyHistory
History is the discovery, collection, organization, and presentation of information about past events. History can also mean the period of time after writing was invented. Scholars who write about history are called historians...
, being used since ancient times to being discovered in laboratories.
In ancient times zinc has been found being used in impure forms as well as in alloys that have been found to be over 2000 years old. In 1817 Cadmium was discovered in Germany as an impurity in zinc carbonate by Friedrich Stromeyer and Karl Samuel Leberecht Hermann
Karl Samuel Leberecht Hermann
Karl Samuel Leberecht Hermann was a German chemist who independently discovered cadmium in 1817.Cadmium was discovered in 1817 by a physician, Friedrich Stromeyer . The element was first found in the condensation of vapors that rose out of a furnace in which zinc oxide was being roasted...
. Mercury has been found in Egypt
Egypt
Egypt , officially the Arab Republic of Egypt, Arabic: , is a country mainly in North Africa, with the Sinai Peninsula forming a land bridge in Southwest Asia. Egypt is thus a transcontinental country, and a major power in Africa, the Mediterranean Basin, the Middle East and the Muslim world...
ian tombs which have been dated to 1500 BC, where mercury was in cosmetics. It was also used by the ancient Chinese who believed it would improve and prolong health.
The heaviest know group 12 element, copernicium was first created on February 9, 1996, at the Gesellschaft für Schwerionenforschung
Gesellschaft für Schwerionenforschung
The GSI Helmholtz Centre for Heavy Ion Research GmbH in the Wixhausen suburb of Darmstadt, Germany is a federally and state co-funded heavy ion research center. The current director of GSI is Horst Stöcker who succeeded Walter F...
(GSI) located in Darmstadt
Darmstadt
Darmstadt is a city in the Bundesland of Hesse in Germany, located in the southern part of the Rhine Main Area.The sandy soils in the Darmstadt area, ill-suited for agriculture in times before industrial fertilisation, prevented any larger settlement from developing, until the city became the seat...
, Germany
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
by Sigurd Hofmann, Victor Ninov
Victor Ninov
Victor Ninov is a former researcher in the nuclear chemistry group at Lawrence Berkeley National Laboratory who was alleged to have fabricated the evidence used to claim the creation of ununoctium and ununhexium....
et al. It was then officially named on February 19, 2010 by the International Union of Pure and Applied Chemistry
International Union of Pure and Applied Chemistry
The International Union of Pure and Applied Chemistry is an international federation of National Adhering Organizations that represents chemists in individual countries. It is a member of the International Council for Science . The international headquarters of IUPAC is located in Zürich,...
.
Occurrence
Like in most other d-blockD-block
The d-block is the portion of the periodic table that contains the element groups 3-12. These groups correspond to the filling of the atomic d-orbital subshell, with electron configurations ranging from s2d1 to s2d10...
groups the abundance in Earth's crust
Abundance of elements in Earth's crust
The table shows the abundance of elements in Earth's crust. Numbers show percentage or parts per million in mass; 10,000 ppm = 1%.Note that numbers are estimates, and they will vary depending on source and method of estimation. Order of magnitude of data can roughly be relied upon.The table shows...
decreases with higher atomic number, and so the zinc is with 65 parts per million (ppm) the most abundant in the group while cadmium with 0.1 ppm and mercury with 0.040 ppm are orders of magnitude less abundant. Copernicium, as a synthetic element with a half-life
Half-life
Half-life, abbreviated t½, is the period of time it takes for the amount of a substance undergoing decay to decrease by half. The name was originally used to describe a characteristic of unstable atoms , but it may apply to any quantity which follows a set-rate decay.The original term, dating to...
of a few minutes, may only be present in the laboratories where it was produced.
The commercially most important minerals of group 12 elements are sulfide minerals, for example sphalerite
Sphalerite
Sphalerite is a mineral that is the chief ore of zinc. It consists largely of zinc sulfide in crystalline form but almost always contains variable iron. When iron content is high it is an opaque black variety, marmatite. It is usually found in association with galena, pyrite, and other sulfides...
(ZnS), greenockite
Greenockite
Greenockite is a rare cadmium mineral that consists of cadmium sulfide, CdS, in crystalline form. Greenockite crystallizes in the hexagonal system. It occurs as massive encrustations and as six-sided pyramidal crystals which vary in color from a honey yellow through shades of red to brown...
(CdS) and cinnabar
Cinnabar
Cinnabar or cinnabarite , is the common ore of mercury.-Word origin:The name comes from κινναβαρι , a Greek word most likely applied by Theophrastus to several distinct substances...
(HgS). While mercury and zinc minerals are found in large enough quantities to be mined, cadmium is too similar to zinc and therefore is always present in small quantities in zinc ores.
Production
Zinc is the fourth most common metal in use, trailing only iron, aluminium, and copper with an annual production of about 10 million tonnes. Worldwide, 95% of the zinc is mined from sulfidicSulfide
A sulfide is an anion of sulfur in its lowest oxidation state of 2-. Sulfide is also a slightly archaic term for thioethers, a common type of organosulfur compound that are well known for their bad odors.- Properties :...
ore deposits, in which sphalerite ZnS is nearly always mixed with the sulfides of copper, lead and iron. Zinc metal is produced using extractive metallurgy
Extractive metallurgy
Extractive metallurgy is the study of the processes used in the separation and concentration of raw materials. The field is an applied science, covering all aspects of the physical and chemical processes used to produce mineral-containing and metallic materials, sometimes for direct use as a...
. Roasting
Roasting (metallurgy)
Roasting is a step in the processing of certain ores. More specifically, roasting is a metallurgical process involving gas–solid reactions at elevated temperatures with the goal of purifying the metal component. Often before roasting, the ore has already been partially purified, e.g. by froth...
converts the zinc sulfide concentrate produced during processing to zinc oxide: For further processing two basic methods are used: pyrometallurgy
Pyrometallurgy
Pyrometallurgy is a branch of extractive metallurgy. It consists of the thermal treatment of minerals and metallurgical ores and concentrates to bring about physical and chemical transformations in the materials to enable recovery of valuable metals...
or electrowinning
Electrowinning
Electrowinning, also called electroextraction, is the electrodeposition of metals from their ores that have been put in solution or liquefied. Electrorefining uses a similar process to remove impurities from a metal. Both processes use electroplating on a large scale and are important techniques...
. Pyrometallurgy processing reduces zinc oxide with carbon
Carbon
Carbon is the chemical element with symbol C and atomic number 6. As a member of group 14 on the periodic table, it is nonmetallic and tetravalent—making four electrons available to form covalent chemical bonds...
or carbon monoxide
Carbon monoxide
Carbon monoxide , also called carbonous oxide, is a colorless, odorless, and tasteless gas that is slightly lighter than air. It is highly toxic to humans and animals in higher quantities, although it is also produced in normal animal metabolism in low quantities, and is thought to have some normal...
at 950 °C (1,742 °F) into the metal, which is distilled as zinc vapor. The zinc vapor is collected in a condenser. Electrowinning processing leaches zinc from the ore concentrate by sulfuric acid
Sulfuric acid
Sulfuric acid is a strong mineral acid with the molecular formula . Its historical name is oil of vitriol. Pure sulfuric acid is a highly corrosive, colorless, viscous liquid. The salts of sulfuric acid are called sulfates...
: After this step electrolysis
Electrolysis
In chemistry and manufacturing, electrolysis is a method of using a direct electric current to drive an otherwise non-spontaneous chemical reaction...
is used to produce zinc metal.
Cadmium is a common impurity in zinc
Zinc
Zinc , or spelter , is a metallic chemical element; it has the symbol Zn and atomic number 30. It is the first element in group 12 of the periodic table. Zinc is, in some respects, chemically similar to magnesium, because its ion is of similar size and its only common oxidation state is +2...
ores, and it is most isolated during the production of zinc. Some zinc ores concentrates from sulfidic zinc ores contain up to 1.4% of cadmium. Cadmium is isolated from the zinc produced from the flue dust by vacuum distillation
Vacuum distillation
Vacuum distillation is a method of distillation whereby the pressure above the liquid mixture to be distilled is reduced to less than its vapor pressure causing evaporation of the most volatile liquid...
if the zinc is smelted, or cadmium sulfate is precipitated out of the electrolysis solution.
The richest mercury ores contain up to 2.5% mercury by mass, and even the leanest concentrated deposits are at least 0.1% mercury, with cinnabar (HgS) being the most common ore in the deposits.
Mercury is extracted by heating cinnabar in a current of air and condensing the vapor.
Super-heavy elements such as copernicium are produced by bombarding lighter elements in particle accelerator
Particle accelerator
A particle accelerator is a device that uses electromagnetic fields to propel charged particles to high speeds and to contain them in well-defined beams. An ordinary CRT television set is a simple form of accelerator. There are two basic types: electrostatic and oscillating field accelerators.In...
s that induces fusion reactions. Whereas most of the isotopes of rutherfordium can be synthesized directly this way, some heavier ones have only been observed as decay products of elements with higher atomic number
Atomic number
In chemistry and physics, the atomic number is the number of protons found in the nucleus of an atom and therefore identical to the charge number of the nucleus. It is conventionally represented by the symbol Z. The atomic number uniquely identifies a chemical element...
s. The first fusion reaction to produce copernicium was performed by GSI in 1996, who reported the detection of two decay chains of copernicium-277.
- + → +
Up to 2011 only a small number of atoms have been prepared.
Applications
Due to the physical similarities which they share, the group 12 elements can be found in many common situations. Zinc and cadmium are commonly used as anti-corrosion agents as they will attract all local oxidation until they completely corrode. These protective coatings can be applied to other metals through by hot-dip galvanizingHot-dip galvanizing
Hot-dip galvanizing is a form of galvanization. It is the process of coating iron, steel, or aluminum with a thin zinc layer, by passing the metal through a molten bath of zinc at a temperature of around 860 °F...
a substance into the molten form of the metal, or through the process of electroplating
Electroplating
Electroplating is a plating process in which metal ions in a solution are moved by an electric field to coat an electrode. The process uses electrical current to reduce cations of a desired material from a solution and coat a conductive object with a thin layer of the material, such as a metal...
which may be passivated by the use of chromate
Chromate
Chromate salts contain the chromate anion, CrO42−. Dichromate salts contain the dichromate anion, Cr2O72−. They are oxyanions of chromium in the oxidation state +6. They are moderately strong oxidizing agents.- Chemical properties :...
salts.
Group 12 elements are also used in electrochemistry
Electrochemistry
Electrochemistry is a branch of chemistry that studies chemical reactions which take place in a solution at the interface of an electron conductor and an ionic conductor , and which involve electron transfer between the electrode and the electrolyte or species in solution.If a chemical reaction is...
as they may act as an alternative to the standard hydrogen electrode
Standard hydrogen electrode
The standard hydrogen electrode , is a redox electrode which forms the basis of the thermodynamic scale of oxidation-reduction potentials...
in addition to being a secondary reference electrode. Zinc is commonly used as and anode in batteries and fuel cells; whereas, cadmium is commonly used in recharable nickle-cadmium batteries.
Biological role
The group 12 elements have multiple effects on biological organisms as cadmium and mercury are toxic while zinc is required by most plants and animals in trace amounts. Zinc is required by most organisms in trace amountsTrace element
In analytical chemistry, a trace element is an element in a sample that has an average concentration of less than 100 parts per million measured in atomic count, or less than 100 micrograms per gram....
as it is present in enzymes where it is often present as a catalytic agent for enzyme-directed reactions. In large amounts zinc may be toxic to biological organisms as it prevents cells from absorbing copper and iron.
Mercury and cadmium are toxic and may cause environmental damage if they enter rivers or rain water. This may result in contaminated crops as well as the bioaccumulation
Bioaccumulation
Bioaccumulation refers to the accumulation of substances, such as pesticides, or other organic chemicals in an organism. Bioaccumulation occurs when an organism absorbs a toxic substance at a rate greater than that at which the substance is lost...
of mercury in a food chain leading to an increase in illnesses caused by mercury
Mercury poisoning
Mercury poisoning is a disease caused by exposure to mercury or its compounds. Mercury is a heavy metal occurring in several forms, all of which can produce toxic effects in high enough doses...
and cadmium poisoning
Cadmium poisoning
Cadmium is an extremely toxic metal commonly found in industrial workplaces. Due to its low permissible exposure limit, overexposures may occur even in situations where trace quantities of cadmium are found. Cadmium is used extensively in electroplating, although the nature of the operation does...
.