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51-467: Typically Gâteau Basque is constructed from layers of a butter-sugar wheat flour pastry dough (in this case pâte sablée , not brisée ) with a filling of either black cherry jam or almond or vanilla pastry cream . It has been argued that only black Xapata cherries native to the Basque Country should be used. The type of dough used may vary a little. If butter is warmed before mixing with flour

102-398: A −C≡N functional group are called nitriles . An example of a nitrile is acetonitrile , CH 3 −C≡N . Nitriles usually do not release cyanide ions. A functional group with a hydroxyl −OH and cyanide −CN bonded to the same carbon atom is called cyanohydrin ( R 2 C(OH)CN ). Unlike nitriles, cyanohydrins do release poisonous hydrogen cyanide . Cyanide is basic. The p K

153-408: A of hydrogen cyanide is 9.21. Thus, addition of acids stronger than hydrogen cyanide to solutions of cyanide salts releases hydrogen cyanide . Cyanide is unstable in water, but the reaction is slow until about 170 °C. It undergoes hydrolysis to give ammonia and formate , which are far less toxic than cyanide: Cyanide hydrolase is an enzyme that catalyzes this reaction. Because of

204-483: A tailing pond or spent heap, the recoverable gold having been removed. The metal is recovered from the "pregnant solution" by reduction with zinc dust or by adsorption onto activated carbon . This process can result in environmental and health problems. A number of environmental disasters have followed the overflow of tailing ponds at gold mines. Cyanide contamination of waterways has resulted in numerous cases of human and aquatic species mortality. Aqueous cyanide

255-483: A height of 15–24 metres (49–79 feet). The leaves are 5–13 centimetres (2–5 inches) long, ovate-lanceolate in shape, with finely toothed margins. Fall leaf color is yellow to red. Flowers are small, white and 5-petalled, in racemes 10–15 cm (4–6 in) long which contain several dozen flowers. The flowers give rise to reddish-black "berries" ( drupes ) fed on by birds, 5–10 millimetres ( 1 ⁄ 4 – 3 ⁄ 8  in) in diameter. For about its first decade

306-493: A subgenus also including Eurasian bird cherry ( P. padus ) and chokecherry ( P. virginiana ). The species is widespread and common in North America and South America. Black cherry is closely related to the chokecherry ( P. virginiana ); chokecherry, however, tends to be shorter (a shrub or small tree) and has smaller, less glossy leaves. Prunus serotina is a medium-sized, fast-growing forest tree growing to

357-455: Is a chemical compound that contains a C≡N functional group . This group, known as the cyano group , consists of a carbon atom triple-bonded to a nitrogen atom. In inorganic cyanides, the cyanide group is present as the cyanide anion C≡N . This anion is extremely poisonous . Soluble salts such as sodium cyanide (NaCN) and potassium cyanide (KCN) are highly toxic. Hydrocyanic acid , also known as hydrogen cyanide, or HCN,

408-532: Is a reductant and is oxidized by strong oxidizing agents such as molecular chlorine ( Cl 2 ), hypochlorite ( ClO ), and hydrogen peroxide ( H 2 O 2 ). These oxidizers are used to destroy cyanides in effluents from gold mining . The cyanide anion reacts with transition metals to form M-CN bonds . This reaction is the basis of cyanide's toxicity. The high affinities of metals for this anion can be attributed to its negative charge, compactness, and ability to engage in π-bonding. Among

459-421: Is a gas, making it more indiscriminately dangerous, however it is lighter than air and rapidly disperses up into the atmosphere, which makes it ineffective as a chemical weapon . Because of the high stability of their complexation with iron , ferrocyanides ( Sodium ferrocyanide E535, Potassium ferrocyanide E536, and Calcium ferrocyanide E538 ) do not decompose to lethal levels in the human body and are used in

510-423: Is a highly volatile liquid that is produced on a large scale industrially. It is obtained by acidification of cyanide salts. Organic cyanides are usually called nitriles . In nitriles, the −C≡N group is linked by a single covalent bond to carbon. For example, in acetonitrile ( CH 3 −C≡N ), the cyanide group is bonded to methyl ( −CH 3 ). Although nitriles generally do not release cyanide ions,

561-437: Is around 560 kg/m (35  lb/cu ft ). Prunus serotina was widely introduced into Western and Central Europe as an ornamental tree in the mid-20th century, where it has become locally naturalized . It has acted as an invasive species there, negatively affecting forest community biodiversity and regeneration. Cyanide In chemistry , cyanide (from Greek kyanos  ' dark blue ')

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612-428: Is hydrolyzed rapidly, especially in sunlight. It can mobilize some heavy metals such as mercury if present. Gold can also be associated with arsenopyrite (FeAsS), which is similar to iron pyrite (fool's gold), wherein half of the sulfur atoms are replaced by arsenic . Gold-containing arsenopyrite ores are similarly reactive toward inorganic cyanide. The second major application of alkali metal cyanides (after mining)

663-418: Is in the production of CN-containing compounds, usually nitriles. Acyl cyanides are produced from acyl chlorides and cyanide. Cyanogen , cyanogen chloride , and the trimer cyanuric chloride are derived from alkali metal cyanides. The cyanide compound sodium nitroprusside is used mainly in clinical chemistry to measure urine ketone bodies mainly as a follow-up to diabetic patients. On occasion, it

714-422: Is mainly produced for the mining of silver and gold : It helps dissolve these metals allowing separation from the other solids. In the cyanide process , finely ground high-grade ore is mixed with the cyanide (at a ratio of about 1:500 parts NaCN to ore); low-grade ores are stacked into heaps and sprayed with a cyanide solution (at a ratio of about 1:1000 parts NaCN to ore). The precious metals are complexed by

765-417: Is traditional to mark a Basque cross on the top if the cake is filled with black cherry jam, or to use a crosshatch pattern on top if filled with pastry cream. The origins of Gâteau Basque are tied strongly with the town of Cambo-les-Bains , Labourd . It may have originally been made with bread and called bistochak in the 18th century. The fishermen took it out to sea. The first known commercialisation of

816-415: Is used in emergency medical situations to produce a rapid decrease in blood pressure in humans; it is also used as a vasodilator in vascular research. The cobalt in artificial vitamin B 12 contains a cyanide ligand as an artifact of the purification process; this must be removed by the body before the vitamin molecule can be activated for biochemical use. During World War I , a copper cyanide compound

867-443: Is used to achieve a blue color on cast bronze sculptures during the final finishing stage of the sculpture. On its own, it will produce a very dark shade of blue and is often mixed with other chemicals to achieve the desired tint and hue. It is applied using a torch and paint brush while wearing the standard safety equipment used for any patina application: rubber gloves, safety glasses, and a respirator. The actual amount of cyanide in

918-460: Is used to measure the temperature of interstellar gas clouds . Hydrogen cyanide is produced by the combustion or pyrolysis of certain materials under oxygen-deficient conditions. For example, it can be detected in the exhaust of internal combustion engines and tobacco smoke. Certain plastics , especially those derived from acrylonitrile , release hydrogen cyanide when heated or burnt. In IUPAC nomenclature , organic compounds that have

969-712: The Midwest , it is seen growing mostly in old fields with other sunlight-loving species, such as black walnut , black locust , and hackberry . Gleason and Cronquist (1991) describe P. serotina as "[f]ormerly a forest tree, now abundant as a weed-tree of roadsides, waste land, and forest-margins". It is a moderately long-lived tree, with ages of up to 258 years known, though it is prone to storm damage, with branches breaking easily; any decay resulting, however, only progresses slowly. Fruit production begins around 10 years of age, but does not become heavy until 30 years and continues up to 100 years or more. Germination rates are high, and

1020-448: The bark of a black cherry tree is thin, smooth, and banded, resembling a birch . A mature tree has very broken, dark gray to black bark. The leaves are long and shiny, resembling a sourwood 's. An almond-like odour is released when a young twig is scratched and held close to the nose, revealing minute amounts of cyanide compounds produced and stored by the plant as a defense mechanism against herbivores . Like apricots and apples,

1071-648: The cyanohydrins do and are thus toxic. The cyanide ion C≡N is isoelectronic with carbon monoxide C≡O and with molecular nitrogen N≡N. A triple bond exists between C and N. The negative charge is concentrated on carbon C. Cyanides are produced by certain bacteria , fungi , and algae . It is an antifeedant in a number of plants. Cyanides are found in substantial amounts in certain seeds and fruit stones, e.g., those of bitter almonds , apricots , apples , and peaches . Chemical compounds that can release cyanide are known as cyanogenic compounds. In plants, cyanides are usually bound to sugar molecules in

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1122-517: The heart , are particularly affected. This is an example of histotoxic hypoxia . The most hazardous compound is hydrogen cyanide , which is a gas and kills by inhalation. For this reason, an air respirator supplied by an external oxygen source must be worn when working with hydrogen cyanide. Hydrogen cyanide is produced by adding acid to a solution containing a cyanide salt. Alkaline solutions of cyanide are safer to use because they do not evolve hydrogen cyanide gas. Hydrogen cyanide may be produced in

1173-412: The mitochondria of eukaryotic cells. It attaches to the iron within this protein. The binding of cyanide to this enzyme prevents transport of electrons from cytochrome c to oxygen. As a result, the electron transport chain is disrupted, meaning that the cell can no longer aerobically produce ATP for energy. Tissues that depend highly on aerobic respiration , such as the central nervous system and

1224-530: The United States to kill coyotes and other canids. Cyanide is also used for pest control in New Zealand , particularly for possums , an introduced marsupial that threatens the conservation of native species and spreads tuberculosis amongst cattle. Possums can become bait shy but the use of pellets containing the cyanide reduces bait shyness. Cyanide has been known to kill native birds, including

1275-407: The antidote was to generate a large pool of ferric iron ( Fe ) to compete for cyanide with cytochrome a 3 (so that cyanide will bind to the antidote rather than the enzyme). The nitrites oxidize hemoglobin to methemoglobin , which competes with cytochrome oxidase for the cyanide ion. Cyanmethemoglobin is formed and the cytochrome oxidase enzyme is restored. The major mechanism to remove

1326-501: The bamboo, has developed a high tolerance to cyanide. The hydrogenase enzymes contain cyanide ligands attached to iron in their active sites. The biosynthesis of cyanide in the NiFe hydrogenases proceeds from carbamoyl phosphate , which converts to cysteinyl thiocyanate , the CN donor. The cyanide radical CN has been identified in interstellar space . Cyanogen , (CN) 2 ,

1377-458: The blue color to blueprints , bluing , and cyanotypes . The principal process used to manufacture cyanides is the Andrussow process in which gaseous hydrogen cyanide is produced from methane and ammonia in the presence of oxygen and a platinum catalyst . Sodium cyanide, the precursor to most cyanides, is produced by treating hydrogen cyanide with sodium hydroxide : Among

1428-697: The cake was by Marianne Hirigoyen in Cambo in the first half of the 19th century. Later editions were flavoured with rum, brought back to France by Basques from the West Indies. The Gâteau Basque Festival ( Fête du Gâteau Basque ) is organized each year in Cambo-les-Bains. Eguzkia ("sun" in Basque), an association to promote quality Basque cake, was founded in France in 1994. There is a museum dedicated to

1479-694: The cake, Le musée du Gâteau Basque , in Sare , Labourd. Black cherry Prunus serotina , commonly called black cherry , wild black cherry , rum cherry , or mountain black cherry , is a deciduous tree or shrub in the rose family Rosaceae . Despite being called black cherry, it is not very closely related to the commonly cultivated cherries, such as sweet cherry ( P. avium ), sour cherry ( P. cerasus ) and Japanese flowering cherries ( P. serrulata , P. speciosa , P. sargentii , P. incisa , etc.), which belong to Prunus subg. Cerasus . Instead, P. serotina belongs to Prunus subg. Padus ,

1530-639: The caterpillars of more than 450 species of butterflies and moths, including those of the eastern tiger swallowtail ( Papilio glaucus ) , cherry gall azure ( Celastrina serotina ) , viceroy ( Limenitis archippus ) , and red-spotted purple/white admiral ( Limenitis arthemis ) butterflies and the cecropia ( Hyalophora cecropia ) , promethea ( Callosamia promethea ) , polyphemus ( Antheraea polyphemus ) , small-eyed sphinx ( Paonias myops ) , wild cherry sphinx ( Sphinx drupiferarum ) , banded tussock ( Halysidota tessellaris ) , spotted apatelodes ( Apatelodes torrefacta ) , and band-edged prominent moths. Deer browse

1581-512: The combustion of polyurethanes ; for this reason, polyurethanes are not recommended for use in domestic and aircraft furniture. Oral ingestion of a small quantity of solid cyanide or a cyanide solution of as little as 200 mg, or exposure to airborne cyanide of 270 ppm , is sufficient to cause death within minutes. Organic nitriles do not readily release cyanide ions, and so have low toxicities. By contrast, compounds such as trimethylsilyl cyanide (CH 3 ) 3 SiCN readily release HCN or

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1632-420: The cyanide anions to form soluble derivatives, e.g., [Ag(CN) 2 ] (dicyanoargentate(I)) and [Au(CN) 2 ] (dicyanoaurate(I)). Silver is less "noble" than gold and often occurs as the sulfide, in which case redox is not invoked (no O 2 is required). Instead, a displacement reaction occurs: The "pregnant liquor" containing these ions is separated from the solids, which are discarded to

1683-410: The cyanide anion's high nucleophilicity , cyano groups are readily introduced into organic molecules by displacement of a halide group (e.g., the chloride on methyl chloride ). In general, organic cyanides are called nitriles. In organic synthesis, cyanide is a C-1 synthon ; i.e., it can be used to lengthen a carbon chain by one, while retaining the ability to be functionalized . The cyanide ion

1734-602: The cyanide from the body is by enzymatic conversion to thiocyanate by the mitochondrial enzyme rhodanese . Thiocyanate is a relatively non-toxic molecule and is excreted by the kidneys. To accelerate this detoxification, sodium thiosulfate is administered to provide a sulfur donor for rhodanese , needed in order to produce thiocyanate. Minimum risk levels (MRLs) may not protect for delayed health effects or health effects acquired following repeated sublethal exposure, such as hypersensitivity, asthma , or bronchitis . MRLs may be revised after sufficient data accumulates. Cyanide

1785-525: The cyanide ion upon contact with water. Hydroxocobalamin reacts with cyanide to form cyanocobalamin , which can be safely eliminated by the kidneys. This method has the advantage of avoiding the formation of methemoglobin (see below). This antidote kit is sold under the brand name Cyanokit and was approved by the U.S. FDA in 2006. An older cyanide antidote kit included administration of three substances: amyl nitrite pearls (administered by inhalation), sodium nitrite , and sodium thiosulfate . The goal of

1836-399: The dough will be called pâte sucrée . If it is cold the mixing process will require more work and the dough is called pâte sablée (it is crumblier). The resulting textures are a little different but mostly for the initiated taster. The flour used is a soft wheat flour with little mineral content (that is, a refined flour, common pastry/cake flour) The proportion of sugar used also varies. But

1887-496: The endangered kiwi . Cyanide is also effective for controlling the dama wallaby , another introduced marsupial pest in New Zealand. A licence is required to store, handle and use cyanide in New Zealand. Cyanides are used as insecticides for fumigating ships. Cyanide salts are used for killing ants, and have in some places been used as rat poison (the less toxic poison arsenic is more common). Potassium ferrocyanide

1938-473: The enzymes needed to convert them to cyanide, so the flesh is safe to eat. The foliage, particularly when wilted, also contains cyanogenic glycosides, which convert to hydrogen cyanide if eaten by animals. Farmers are recommended to remove any trees that fall in a field containing livestock, because the wilted leaves could poison the animals. Removal is not always practical, though, because these trees often grow in very large numbers on farms, taking advantage of

1989-568: The foliage. Hyphantria cunea can inhibit the impact of cyanide within the plants' leaves due to its alkaline stomach acid. The eastern tent caterpillar defoliates entire groves some springs. Prunus serotina subsp. capuli was cultivated in Central and South America well before European contact. Known as capolcuahuitl in Nahuatl (the source of the capuli epithet), it was an important food in pre-Columbian Mexico. Native Americans ate

2040-420: The food industry as, e.g., an anticaking agent in table salt . Cyanide is quantified by potentiometric titration , a method widely used in gold mining. It can also be determined by titration with silver ion. Some analyses begin with an air-purge of an acidified boiling solution, sweeping the vapors into a basic absorber solution. The cyanide salt absorbed in the basic solution is then analyzed. Because of

2091-417: The form of cyanogenic glycosides and defend the plant against herbivores . Cassava roots (also called manioc), an important potato -like food grown in tropical countries (and the base from which tapioca is made), also contain cyanogenic glycosides. The Madagascar bamboo Cathariostachys madagascariensis produces cyanide as a deterrent to grazing. In response, the golden bamboo lemur , which eats

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2142-433: The fruit. Edible raw, the fruit is also made into jelly, and the juice can be used as a drink mixer, hence the common name 'rum cherry'. Prunus serotina timber is valuable; perhaps the premier cabinetry timber of the U.S., traded as "cherry". High quality cherry timber is known for its strong orange hues, tight grain and high price. Low-quality wood, as well as the sap wood, can be more tan. Its density when dried

2193-407: The light brought about by mowing and grazing. Entire fencerows can be lined with this poisonous tree, making it difficult to monitor all the branches falling into the grazing area. Black cherry is a leading cause of livestock illness, and grazing animals' access to it should be limited. Prunus serotina has the following subspecies and varieties : Prunus serotina is a pioneer species . In

2244-488: The mixture varies according to the recipes used by each foundry. Cyanide is also used in jewelry -making and certain kinds of photography such as sepia toning . Although usually thought to be toxic, cyanide and cyanohydrins increase germination in various plant species. Deliberate cyanide poisoning of humans has occurred many times throughout history. Common salts such as sodium cyanide are involatile but water-soluble, so are poisonous by ingestion. Hydrogen cyanide

2295-435: The most important cyanide coordination compounds are the potassium ferrocyanide and the pigment Prussian blue , which are both essentially nontoxic due to the tight binding of the cyanides to a central iron atom. Prussian blue was first accidentally made around 1706, by heating substances containing iron and carbon and nitrogen, and other cyanides made subsequently (and named after it). Among its many uses, Prussian blue gives

2346-415: The most toxic cyanides are hydrogen cyanide (HCN), sodium cyanide (NaCN), potassium cyanide (KCN), and calcium cyanide (Ca(CN)₂). These compounds are extremely poisonous and require careful handling to avoid severe health risks. The cyanide anion is an inhibitor of the enzyme cytochrome c oxidase (also known as aa 3 ), the fourth complex of the electron transport chain found in the inner membrane of

2397-460: The notorious toxicity of cyanide, many methods have been investigated. Benzidine gives a blue coloration in the presence of ferricyanide . Iron(II) sulfate added to a solution of cyanide, such as the filtrate from the sodium fusion test , gives prussian blue . A solution of para -benzoquinone in DMSO reacts with inorganic cyanide to form a cyano phenol , which is fluorescent . Illumination with

2448-534: The principle of this cake is having a soft shortbread-type dough 3 to 6 mm thick filled with an almond pastry cream, also called frangipane , and with a shiny egg-coating. The dough is rolled out like a double crust pie and filled with jam or pastry cream. Similar to the Boston cream pie , which is a cake and not a pie, the Gâteau Basque dough produces a crumb-textured pastry that is chewy and tender. It

2499-449: The seeds are widely dispersed by birds and bears who eat the fruit and then excrete them. Some seeds however may remain in the soil bank and not germinate for as long as three years. All Prunus species have hard seeds that benefit from scarification to germinate (which in nature is produced by passing through an animal's digestive tract). The tree is hardy and can tolerate poor soils and oceanic salt sprays [1] . P. serotina hosts

2550-476: The seeds of black cherries contain cyanogenic glycosides (compounds that can be converted into cyanide ), such as amygdalin . These compounds release hydrogen cyanide when the seed is ground or minced, which releases enzymes that break down the compounds. These enzymes include amygdalin beta-glucosidase , prunasin beta-glucosidase and mandelonitrile lyase . In contrast, although the flesh of black cherries also contains these glycosides, it does not contain

2601-509: Was briefly used by Japanese physicians for the treatment of tuberculosis and leprosy . Cyanides are illegally used to capture live fish near coral reefs for the aquarium and seafood markets. The practice is controversial, dangerous, and damaging but is driven by the lucrative exotic fish market. Poachers in Africa have been known to use cyanide to poison waterholes, to kill elephants for their ivory. M44 cyanide devices are used in

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