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60-397: In 1816 he published Précis élementaire de Physiologie which described an experiment first illustrating the concept of empty calories : His most important contribution to science was also his most disputed. Contemporaneous to Sir Charles Bell , Magendie conducted a number of experiments on the nervous system, in particular verifying the differentiation between sensory and motor nerves in

120-409: A condenser . Some alchemists called this zinc oxide lana philosophica , Latin for "philosopher's wool", because it collected in wooly tufts, whereas others thought it looked like white snow and named it nix album . The name of the metal was probably first documented by Paracelsus , a Swiss-born German alchemist, who referred to the metal as "zincum" or "zinken" in his book Liber Mineralium II , in

180-428: A gamma ray . Zn has three excited metastable states and Zn has two. The isotopes Zn , Zn , Zn and Zn each have only one excited metastable state. The most common decay mode of a radioisotope of zinc with a mass number lower than 66 is electron capture . The decay product resulting from electron capture is an isotope of copper. The most common decay mode of

240-518: A by-product of smelting sulfide ores. Zinc in such remnants in smelting ovens was usually discarded as it was thought to be worthless. The manufacture of brass was known to the Romans by about 30 BC. They made brass by heating powdered calamine (zinc silicate or carbonate), charcoal and copper together in a crucible. The resulting calamine brass was then either cast or hammered into shape for use in weaponry. Some coins struck by Romans in

300-463: A diet that is both balanced and within TDEE , and so readily create an unhealthy diet. The lack of complete nutrition found in high energy foods was first scientifically tested by French physiologist François Magendie , who experimented on dogs and described the process in his book Précis élémentaire de Physiologie . He demonstrated that the eating of nothing but sugar, olive oil, or butter could be

360-400: A half-life of 243.66 days, is the least active radioisotope, followed by Zn with a half-life of 46.5 hours. Zinc has 10 nuclear isomers , of which Zn has the longest half-life, 13.76 h. The superscript m indicates a metastable isotope. The nucleus of a metastable isotope is in an excited state and will return to the ground state by emitting a photon in the form of

420-433: A larger amount of calorie-rich, essential nutrient-poor foods. Dietitians and other healthcare professionals can prevent malnutrition by designing eating programs and recommending dietary modifications according to each patient's needs. The USDA advises the following levels of empty calorie consumption as an upper limit for individuals who engage in 30 minutes or less of moderate exercise daily. Zinc Zinc

480-515: A metal which, when oxidized, produces pushpanjan , thought to be zinc oxide. Zinc mines at Zawar, near Udaipur in India, have been active since the Mauryan period ( c.  322 and 187 BCE). The smelting of metallic zinc here, however, appears to have begun around the 12th century AD. One estimate is that this location produced an estimated million tonnes of metallic zinc and zinc oxide from

540-417: A metal–carbon sigma bond . Cobalticyanide paper (Rinnmann's test for Zn) can be used as a chemical indicator for zinc. 4 g of K 3 Co(CN) 6 and 1 g of KClO 3 is dissolved on 100 ml of water. Paper is dipped in the solution and dried at 100 °C. One drop of the sample is dropped onto the dry paper and heated. A green disc indicates the presence of zinc. Various isolated examples of

600-510: A process in 1758 for calcining zinc sulfide into an oxide usable in the retort process. Prior to this, only calamine could be used to produce zinc. In 1798, Johann Christian Ruberg improved on the smelting process by building the first horizontal retort smelter. Jean-Jacques Daniel Dony built a different kind of horizontal zinc smelter in Belgium that processed even more zinc. Italian doctor Luigi Galvani discovered in 1780 that connecting

660-596: A quantity of what he called "calay" (from the Malay or Hindi word for tin) originating from Malabar off a cargo ship captured from the Portuguese in the year 1596. Libavius described the properties of the sample, which may have been zinc. Zinc was regularly imported to Europe from the Orient in the 17th and early 18th centuries, but was at times very expensive. Metallic zinc was isolated in India by 1300 AD. Before it

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720-401: A radioisotope of zinc with mass number higher than 66 is beta decay (β ), which produces an isotope of gallium . Zinc has an electron configuration of [Ar]3d 4s and is a member of the group 12 of the periodic table . It is a moderately reactive metal and strong reducing agent . The surface of the pure metal tarnishes quickly, eventually forming a protective passivating layer of

780-495: A zinc atom in the reactive center are widespread in biochemistry, such as alcohol dehydrogenase in humans. Consumption of excess zinc may cause ataxia , lethargy , and copper deficiency . In marine biomes, notably within polar regions, a deficit of zinc can compromise the vitality of primary algal communities, potentially destabilizing the intricate marine trophic structures and consequently impacting biodiversity. Brass , an alloy of copper and zinc in various proportions,

840-403: Is a chalcophile , meaning the element is more likely to be found in minerals together with sulfur and other heavy chalcogens , rather than with the light chalcogen oxygen or with non-chalcogen electronegative elements such as the halogens . Sulfides formed as the crust solidified under the reducing conditions of the early Earth's atmosphere. Sphalerite , which is a form of zinc sulfide,

900-475: Is a chemical element with the symbol Zn and atomic number 30. It is a slightly brittle metal at room temperature and has a shiny-greyish appearance when oxidation is removed. It is the first element in group 12 (IIB) of the periodic table . In some respects, zinc is chemically similar to magnesium : both elements exhibit only one normal oxidation state (+2), and the Zn and Mg ions are of similar size. Zinc

960-546: Is being smelted. In Britain, John Lane is said to have carried out experiments to smelt zinc, probably at Landore , prior to his bankruptcy in 1726. In 1738 in Great Britain, William Champion patented a process to extract zinc from calamine in a vertical retort -style smelter. His technique resembled that used at Zawar zinc mines in Rajasthan , but no evidence suggests he visited the Orient. Champion's process

1020-527: Is hard and brittle at most temperatures but becomes malleable between 100 and 150 °C. Above 210 °C, the metal becomes brittle again and can be pulverized by beating. Zinc is a fair conductor of electricity . For a metal, zinc has relatively low melting (419.5 °C) and boiling point (907 °C). The melting point is the lowest of all the d-block metals aside from mercury and cadmium ; for this reason among others, zinc, cadmium, and mercury are often not considered to be transition metals like

1080-464: Is implicated by the formation of a yellow diamagnetic glass by dissolving metallic zinc in molten ZnCl 2 . The [Zn 2 ] core would be analogous to the [Hg 2 ] cation present in mercury (I) compounds. The diamagnetic nature of the ion confirms its dimeric structure. The first zinc(I) compound containing the Zn–Zn bond, (η -C 5 Me 5 ) 2 Zn 2 . Binary compounds of zinc are known for most of

1140-410: Is known as Special High Grade, often abbreviated SHG , and is 99.995% pure. Worldwide, 95% of new zinc is mined from sulfidic ore deposits, in which sphalerite (ZnS) is nearly always mixed with the sulfides of copper, lead and iron. Zinc mines are scattered throughout the world, with the main areas being China, Australia, and Peru. China produced 38% of the global zinc output in 2014. Zinc metal

1200-545: Is necessary for prenatal and postnatal development. It is the second most abundant trace metal in humans after iron and it is the only metal which appears in all enzyme classes . Zinc is also an essential nutrient element for coral growth as it is an important cofactor for many enzymes. Zinc deficiency affects about two billion people in the developing world and is associated with many diseases. In children, deficiency causes growth retardation, delayed sexual maturation, infection susceptibility, and diarrhea . Enzymes with

1260-524: Is necessary for the leaching process. If deposits of zinc carbonate , zinc silicate , or zinc-spinel (like the Skorpion Deposit in Namibia ) are used for zinc production, the roasting can be omitted. For further processing two basic methods are used: pyrometallurgy or electrowinning . Pyrometallurgy reduces zinc oxide with carbon or carbon monoxide at 950 °C (1,740 °F) into

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1320-437: Is produced using extractive metallurgy . The ore is finely ground, then put through froth flotation to separate minerals from gangue (on the property of hydrophobicity ), to get a zinc sulfide ore concentrate consisting of about 50% zinc, 32% sulfur, 13% iron, and 5% SiO 2 . Roasting converts the zinc sulfide concentrate to zinc oxide: The sulfur dioxide is used for the production of sulfuric acid, which

1380-642: Is the 24th most abundant element in Earth's crust and has five stable isotopes . The most common zinc ore is sphalerite (zinc blende), a zinc sulfide mineral. The largest workable lodes are in Australia, Asia, and the United States. Zinc is refined by froth flotation of the ore, roasting , and final extraction using electricity ( electrowinning ). Zinc is an essential trace element for humans, animals, plants and for microorganisms and

1440-532: Is the most heavily mined zinc-containing ore because its concentrate contains 60–62% zinc. Other source minerals for zinc include smithsonite (zinc carbonate ), hemimorphite (zinc silicate ), wurtzite (another zinc sulfide), and sometimes hydrozincite (basic zinc carbonate ). With the exception of wurtzite, all these other minerals were formed by weathering of the primordial zinc sulfides. Identified world zinc resources total about 1.9–2.8 billion tonnes . Large deposits are in Australia, Canada and

1500-469: The metalloids and all the nonmetals except the noble gases . The oxide ZnO is a white powder that is nearly insoluble in neutral aqueous solutions, but is amphoteric , dissolving in both strong basic and acidic solutions. The other chalcogenides ( ZnS , ZnSe , and ZnTe ) have varied applications in electronics and optics. Pnictogenides ( Zn 3 N 2 , Zn 3 P 2 , Zn 3 As 2 and Zn 3 Sb 2 ),

1560-518: The spinal cord of a freshly dissected frog to an iron rail attached by a brass hook caused the frog's leg to twitch. He incorrectly thought he had discovered an ability of nerves and muscles to create electricity and called the effect " animal electricity ". The galvanic cell and the process of galvanization were both named for Luigi Galvani, and his discoveries paved the way for electrical batteries , galvanization, and cathodic protection . Galvani's friend, Alessandro Volta , continued researching

1620-403: The 12th to 16th centuries. Another estimate gives a total production of 60,000 tonnes of metallic zinc over this period. The Rasaratna Samuccaya , written in approximately the 13th century AD, mentions two types of zinc-containing ores: one used for metal extraction and another used for medicinal purposes. Zinc was distinctly recognized as a metal under the designation of Yasada or Jasada in

1680-619: The 16th century. The word is probably derived from the German zinke , and supposedly meant "tooth-like, pointed or jagged" (metallic zinc crystals have a needle-like appearance). Zink could also imply "tin-like" because of its relation to German zinn meaning tin. Yet another possibility is that the word is derived from the Persian word سنگ seng meaning stone. The metal was also called Indian tin , tutanego , calamine , and spinter . German metallurgist Andreas Libavius received

1740-422: The 24th most abundant element. It also makes up 312 ppm of the solar system, where it is the 22nd most abundant element. Typical background concentrations of zinc do not exceed 1 μg/m in the atmosphere; 300 mg/kg in soil; 100 mg/kg in vegetation; 20 μg/L in freshwater and 5 μg/L in seawater. The element is normally found in association with other base metals such as copper and lead in ores . Zinc

1800-570: The Christian era are made of what is probably calamine brass. The oldest known pills were made of the zinc carbonates hydrozincite and smithsonite. The pills were used for sore eyes and were found aboard the Roman ship Relitto del Pozzino , wrecked in 140 BC. The Berne zinc tablet is a votive plaque dating to Roman Gaul made of an alloy that is mostly zinc. The Charaka Samhita , thought to have been written between 300 and 500 AD, mentions

1860-478: The United States, with the largest reserves in Iran . The most recent estimate of reserve base for zinc (meets specified minimum physical criteria related to current mining and production practices) was made in 2009 and calculated to be roughly 480 Mt. Zinc reserves, on the other hand, are geologically identified ore bodies whose suitability for recovery is economically based (location, grade, quality, and quantity) at

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1920-419: The basic zinc carbonate , Zn 5 (OH) 6 (CO 3 ) 2 , by reaction with atmospheric carbon dioxide . Zinc burns in air with a bright bluish-green flame, giving off fumes of zinc oxide . Zinc reacts readily with acids , alkalis and other non-metals. Extremely pure zinc reacts only slowly at room temperature with acids. Strong acids, such as hydrochloric or sulfuric acid , can remove

1980-579: The cause of the death of his test animals within 30 to 40 days. The following foods are often considered to contain mostly empty calories and commonly lead to body weight gain. A diet high in added sugar typically alters behavior to reduce consumption of foods that contain essential nutrients. One study reported that when there was increased consumption of added sugars, nutrients at most risk for deficiency were magnesium and vitamins A , C , E . Intake of these nutrients dropped with each 5% increase in added sugar intake. A diet high in alcohol can have

2040-420: The chromate ZnCrO 4 (one of the few colored zinc compounds) are a few examples of other common inorganic compounds of zinc. Organozinc compounds are those that contain zinc– carbon covalent bonds. Diethylzinc ( (C 2 H 5 ) 2 Zn ) is a reagent in synthetic chemistry. It was first reported in 1848 from the reaction of zinc and ethyl iodide , and was the first compound known to contain

2100-855: The earliest version of the phrase " Lies, damned lies, and statistics ". While arguing against using blood-letting to treat fever , and confronted with statistical numbers he believed to be manufactured, Magendie stated: "Thus the alteration of the truth which is already manifesting itself in the progressive form of lying and perjury, offers us, in the superlative , the statistics." Empty calorie In human nutrition , empty calories are those calories found in foods and beverages (including alcohol) composed primarily or solely of calorie-rich macronutrients such as sugars and fats , but little or no micronutrients , fibre , or protein . Foods composed mostly of empty calories have low nutrient density , meaning few other nutrients relative to their energy content. Empty calories are more difficult to fit into

2160-569: The effect and invented the Voltaic pile in 1800. Volta's pile consisted of a stack of simplified galvanic cells , each being one plate of copper and one of zinc connected by an electrolyte . By stacking these units in series, the Voltaic pile (or "battery") as a whole had a higher voltage, which could be used more easily than single cells. Electricity is produced because the Volta potential between

2220-439: The formation of Zn 2 Cl 2 , a zinc compound with a +1 oxidation state. No compounds of zinc in positive oxidation states other than +1 or +2 are known. Calculations indicate that a zinc compound with the oxidation state of +4 is unlikely to exist. Zn(III) is predicted to exist in the presence of strongly electronegative trianions; however, there exists some doubt around this possibility. But in 2021 another compound

2280-461: The hydroxide Zn(OH) 2 forms as a white precipitate . In stronger alkaline solutions, this hydroxide is dissolved to form zincates ( [Zn(OH) 4 ] ). The nitrate Zn(NO 3 ) 2 , chlorate Zn(ClO 3 ) 2 , sulfate ZnSO 4 , phosphate Zn 3 (PO 4 ) 2 , molybdate ZnMoO 4 , cyanide Zn(CN) 2 , arsenite Zn(AsO 2 ) 2 , arsenate Zn(AsO 4 ) 2 ·8H 2 O and

2340-481: The live dissections that he performed at public lectures in physiology. Richard Martin , an Irish MP , in introducing his famous bill banning animal cruelty in the United Kingdom, described Magendie's public dissection of a greyhound , in which the beast was nailed down ear and paw, half the nerves of its face dissected then left overnight for further dissection, calling Magendie a "disgrace to Society." There

2400-459: The medical Lexicon ascribed to the Hindu king Madanapala (of Taka dynasty) and written about the year 1374. Smelting and extraction of impure zinc by reducing calamine with wool and other organic substances was accomplished in the 13th century in India. The Chinese did not learn of the technique until the 17th century. Alchemists burned zinc metal in air and collected the resulting zinc oxide on

2460-420: The organic laboratory. Zinc is a bluish-white, lustrous, diamagnetic metal, though most common commercial grades of the metal have a dull finish. It is somewhat less dense than iron and has a hexagonal crystal structure , with a distorted form of hexagonal close packing , in which each atom has six nearest neighbors (at 265.9 pm) in its own plane and six others at a greater distance of 290.6 pm. The metal

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2520-525: The passivating layer and the subsequent reaction with the acid releases hydrogen gas. The chemistry of zinc is dominated by the +2 oxidation state. When compounds in this oxidation state are formed, the outer shell s electrons are lost, yielding a bare zinc ion with the electronic configuration [Ar]3d . In aqueous solution an octahedral complex, [Zn(H 2 O) 6 ] is the predominant species. The volatilization of zinc in combination with zinc chloride at temperatures above 285 °C indicates

2580-406: The peroxide ( ZnO 2 ), the hydride ( ZnH 2 ), and the carbide ( ZnC 2 ) are also known. Of the four halides , ZnF 2 has the most ionic character, while the others ( ZnCl 2 , ZnBr 2 , and ZnI 2 ) have relatively low melting points and are considered to have more covalent character. In weak basic solutions containing Zn ions,

2640-399: The remainder, have been found that are 2,500 years old. A possibly prehistoric statuette containing 87.5% zinc was found in a Dacian archaeological site. Strabo writing in the 1st century BC (but quoting a now lost work of the 4th century BC historian Theopompus ) mentions "drops of false silver" which when mixed with copper make brass. This may refer to small quantities of zinc that is

2700-541: The reserve lifetime for zinc has remained unchanged. About 346 million tonnes have been extracted throughout history to 2002, and scholars have estimated that about 109–305 million tonnes are in use. Five stable isotopes of zinc occur in nature, with Zn being the most abundant isotope (49.17% natural abundance ). The other isotopes found in nature are Zn (27.73%), Zn (4.04%), Zn (18.45%), and Zn (0.61%). Several dozen radioisotopes have been characterized. Zn , which has

2760-497: The rest of the d-block metals. Many alloys contain zinc, including brass. Other metals long known to form binary alloys with zinc are aluminium , antimony , bismuth , gold , iron, lead , mercury, silver , tin , magnesium , cobalt , nickel , tellurium , and sodium . Although neither zinc nor zirconium is ferromagnetic , their alloy, ZrZn 2 , exhibits ferromagnetism below 35  K . Zinc makes up about 75  ppm  (0.0075%) of Earth's crust , making it

2820-529: The same crystal structure , and in other circumstances where ionic radius is a determining factor, the chemistry of zinc has much in common with that of magnesium. In other respects, there is little similarity with the late first-row transition metals. Zinc tends to form bonds with a greater degree of covalency and much more stable complexes with N - and S - donors. Complexes of zinc are mostly 4- or 6- coordinate , although 5-coordinate complexes are known. Zinc(I) compounds are very rare. The [Zn 2 ] ion

2880-805: The same effect, although in this case the nutrients at particular risk of deficiency are zinc , vitamin D , thiamine , folate , cyanocobalamin , and selenium . People with ALD also develop sarcopenia , but it is not clear if this is due to chronic low protein intake or the disease, which is known to inhibit muscle protein synthesis. Typically, 90% of energy is expended simply to maintain current weight while idle, but in extremely active individuals physical exercise must be balanced with food intake to maintain healthy body weight. Sedentary individuals and those eating less to lose weight will be subject to malnutrition if they eat food primarily composed of empty calories. In contrast, people who engage in heavier physical activity need more food energy as fuel and can have

2940-598: The second known zinc-containing enzyme in 1955. Zinc is the fourth most common metal in use, trailing only iron , aluminium , and copper with an annual production of about 13 million tonnes. The world's largest zinc producer is Nyrstar , a merger of the Australian OZ Minerals and the Belgian Umicore . About 70% of the world's zinc originates from mining, while the remaining 30% comes from recycling secondary zinc. Commercially pure zinc

3000-462: The spinal cord, the so-called Bell–Magendie law . This led to an intense rivalry, with the British claiming that Bell published his discoveries first and that Magendie stole his experiments. The intensity of this scientific rivalry perhaps can only be compared to that between Isaac Newton and Robert Hooke . Magendie was also a notorious vivisector , shocking even many of his contemporaries with

3060-533: The time of determination. Since exploration and mine development is an ongoing process, the amount of zinc reserves is not a fixed number and sustainability of zinc ore supplies cannot be judged by simply extrapolating the combined mine life of today's zinc mines. This concept is well supported by data from the United States Geological Survey (USGS), which illustrates that although refined zinc production increased 80% between 1990 and 2010,

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3120-423: The two metal plates makes electrons flow from the zinc to the copper and corrode the zinc. The non-magnetic character of zinc and its lack of color in solution delayed discovery of its importance to biochemistry and nutrition. This changed in 1940 when carbonic anhydrase , an enzyme that scrubs carbon dioxide from blood, was shown to have zinc in its active site . The digestive enzyme carboxypeptidase became

3180-498: The use of impure zinc in ancient times have been discovered. Zinc ores were used to make the zinc–copper alloy brass thousands of years prior to the discovery of zinc as a separate element. Judean brass from the 14th to 10th centuries BC contains 23% zinc. Knowledge of how to produce brass spread to Ancient Greece by the 7th century BC, but few varieties were made. Ornaments made of alloys containing 80–90% zinc, with lead, iron, antimony , and other metals making up

3240-721: Was a belief among British physicians, even those who defended animal experimentation, that Magendie purposely subjected his experimental animals to needless torture. A Quaker once visited him, questioning him about vivisection; according to Anne Fagot-Largeault 's inaugural lesson at the College of France, he responded with much patience, argumenting the reasons of animal experimentation. Besides drawing sharp criticism from contemporaries in both Britain and France, Magendie's methods were later criticized by, among others, Charles Darwin and Thomas Henry Huxley . Colin White credits to Magendie

3300-593: Was isolated in Europe, it was imported from India in about 1600 CE. Postlewayt 's Universal Dictionary , a contemporary source giving technological information in Europe, did not mention zinc before 1751 but the element was studied before then. Flemish metallurgist and alchemist P. M. de Respour reported that he had extracted metallic zinc from zinc oxide in 1668. By the start of the 18th century, Étienne François Geoffroy described how zinc oxide condenses as yellow crystals on bars of iron placed above zinc ore that

3360-477: Was known to the ancient Romans and Greeks. The mines of Rajasthan have given definite evidence of zinc production going back to the 6th century BC. The oldest evidence of pure zinc comes from Zawar, in Rajasthan, as early as the 9th century AD when a distillation process was employed to make pure zinc. Alchemists burned zinc in air to form what they called " philosopher's wool " or "white snow". The element

3420-786: Was probably named by the alchemist Paracelsus after the German word Zinke (prong, tooth). German chemist Andreas Sigismund Marggraf is credited with discovering pure metallic zinc in 1746. Work by Luigi Galvani and Alessandro Volta uncovered the electrochemical properties of zinc by 1800. Corrosion -resistant zinc plating of iron ( hot-dip galvanizing ) is the major application for zinc. Other applications are in electrical batteries , small non-structural castings, and alloys such as brass. A variety of zinc compounds are commonly used, such as zinc carbonate and zinc gluconate (as dietary supplements), zinc chloride (in deodorants), zinc pyrithione (anti- dandruff shampoos), zinc sulfide (in luminescent paints), and dimethylzinc or diethylzinc in

3480-421: Was reported with more evidence that had the oxidation state of +3 with the formula ZnBeB 11 (CN) 12 . Zinc chemistry is similar to the chemistry of the late first-row transition metals, nickel and copper, though it has a filled d-shell and compounds are diamagnetic and mostly colorless. The ionic radii of zinc and magnesium happen to be nearly identical. Because of this some of the equivalent salts have

3540-539: Was used as early as the third millennium BC in the Aegean area and the region which currently includes Iraq , the United Arab Emirates , Kalmykia , Turkmenistan and Georgia . In the second millennium BC it was used in the regions currently including West India , Uzbekistan , Iran , Syria , Iraq, and Israel . Zinc metal was not produced on a large scale until the 12th century in India, though it

3600-507: Was used through 1851. German chemist Andreas Marggraf normally gets credit for isolating pure metallic zinc in the West, even though Swedish chemist Anton von Swab had distilled zinc from calamine four years previously. In his 1746 experiment, Marggraf heated a mixture of calamine and charcoal in a closed vessel without copper to obtain a metal. This procedure became commercially practical by 1752. William Champion's brother, John, patented

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