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Carl Scheele
Carl Wilhelm Scheele (, ; 9 December 1742 – 21 May 1786) was a German-Swedish pharmaceutical chemist. Scheele discovered oxygen (although Joseph Priestley published his findings first), and identified the elements molybdenum, tungsten, barium, nitrogen, and chlorine, among others. Scheele discovered organic acids tartaric, oxalic, uric, lactic, and citric, as well as hydrofluoric, hydrocyanic, and arsenic acids. He preferred speaking German to Swedish his whole life, as German was commonly spoken among Swedish pharmacists.Fors, Hjalmar 2008. "Stepping through Science’s Door: C. W. Scheele, from Pharmacist's Apprentice to Man of Science". Ambix 55: 29–49 Biography Scheele was born in Stralsund, in western Pomerania, which at the time was a Swedish Dominion inside the Holy Roman Empire. Scheele's father, Joachim (or Johann) Christian Scheele, was a grain dealer and brewer from a respected Pomeranian family. His mother was Margaretha Eleanore Warnekros. Friends ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xylographer
Woodcut is a relief printing technique in printmaking. An artist carves an image into the surface of a block of wood—typically with Chisel#Gouge, gouges—leaving the printing parts level with the surface while removing the non-printing parts. Areas that the artist cuts away carry no ink, while characters or images at surface level carry the ink to produce the print. The block is cut along the wood grain (unlike wood engraving, where the block is cut in the end-grain). The surface is covered with ink by rolling over the surface with an ink-covered roller (brayer), leaving ink upon the flat surface but not in the non-printing areas. Multiple colours can be printed by keying the paper to a frame around the woodblocks (using a different block for each colour). The art of carving the woodcut can be called ''xylography'', but this is rarely used in English for images alone, although that term and ''xylographic'' are used in connection with block books, which are small books contain ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uric Acid
Uric acid is a heterocyclic compound of carbon, nitrogen, oxygen, and hydrogen with the Chemical formula, formula C5H4N4O3. It forms ions and salts known as urates and acid urates, such as ammonium acid urate. Uric acid is a product of the metabolic breakdown of purine nucleotides, and it is a normal component of urine. Hyperuricemia, High blood concentrations of uric acid can lead to gout and are associated with other medical conditions, including diabetes and the formation of ammonium acid urate kidney stones. Chemistry Uric acid was first isolated from kidney stones in 1776 by Swedish chemist Carl Wilhelm Scheele. In 1882, the Ukrainian chemist Ivan Horbaczewski first synthesized uric acid by melting urea with glycine. Uric acid displays lactam–lactim tautomerism. Uric acid crystallizes in the lactam form, with computational chemistry also indicating that tautomer to be the most stable. Uric acid is a diprotic acid with pKa, p''K''a1 = 5.4 and p''K''a2 =&nbs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phlogiston Theory
The phlogiston theory, a superseded scientific theory, postulated the existence of a fire-like element dubbed phlogiston () contained within combustible bodies and released during combustion. The name comes from the Ancient Greek (''burning up''), from (''flame''). The idea of a substance was first proposed in 1667 by Johann Joachim Becher and later put together more formally in 1697 by Georg Ernst Stahl. Phlogiston theory attempted to explain chemical processes such as combustion and rusting, now collectively known as oxidation. The theory was challenged by the concomitant mass increase and was abandoned before the end of the 18th century following experiments by Antoine Lavoisier in the 1770s and by other scientists. Phlogiston theory led to experiments that ultimately resulted in the identification (), and naming (1777), of oxygen by Joseph Priestley and Antoine Lavoisier, respectively. Theory Phlogiston theory states that ''phlogisticated'' substances contain phlo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Georg Ernst Stahl
Georg Ernst Stahl (22 October 1659Stahl's date of birth is often given erroneously as 1660. The correct date is recorded in the parish register of St. John's church, Ansbach. See – 24 May 1734) was a German chemist, physician and philosopher. He was a supporter of vitalism, and until the late 18th century his works on phlogiston were accepted as an explanation for chemical processes.Ku-ming Chang (2008)"Stahl, Georg Ernst", ''Complete Dictionary of Scientific Biography'', Vol. 24, from Cengage Learning Raised as a son to a Lutheran pastor, he was brought up in a very pious and religious household. From an early age he expressed profound interest in chemistry, by age 15 mastering a set of university lecture notes on chemistry and eventually a difficult treatise by Johann von Löwenstern-Kunckel, Johann Kunckel. He had two wives, who both died from puerperal fever in 1696 and 1706. He also had a son Johnathan and a daughter who died in 1708. He continued to work and publish foll ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Johann Von Löwenstern-Kunckel
Johann Kunckel, awarded Swedish nobility in 1693 under the Swedish name von Löwenstern-Kunckel and the German version of the name Kunckel von Löwenstern (1630 - prob. 20 March 1703), German chemist, was born in 1630 (or 1638), near Rendsburg, his father being alchemist to the court of Holstein. He became chemist and apothecary to the dukes of Lauenburg, and then to the Elector of Saxony, Johann Georg II, who put him in charge of the royal laboratory at Dresden. Intrigues engineered against him caused him to resign this position in 1677, and for a time he lectured on chemistry at Annaberg and Wittenberg. Invited to Berlin by Frederick William, in 1679 he became director of the laboratory and glass works of Brandenburg. In 1688 the king of Sweden, Charles XI, brought him to Stockholm, ennobling him under the name ''von Löwenstern-Kunckel'' in 1693 and making him a member of the Bergskollegium, the Board of Mines. He died probably on 20 March 1703 near Stockholm (other sources ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caspar Neumann (chemist)
Caspar Neumann (or Neuman) (July 11, 1683 – October 20, 1737) was a German chemist and apothecary. Biography Birth and Education Neumann was born at Zullichau,Alexander Chalmers: ''General Biographical Dictionary.'' London, 1812, Vol. 23, p. 103. in the Electorate of Brandenburg, July 11, 1683. He was first educated in music by his father, but being orphaned at age 12, he apprenticed to his godfather, the apothecary, Johannes Romke. Completing his apprenticeship in 1701, he commenced practice at Unruhstadt, or Kargowa, in Poland.Alexander Kraft: ''On Two Letters from Caspar Neumann to John Woodward Revealing the Secret Method for Preparation of Prussian Blue.'' p.137. Career After three years in Kargowa, he went to Berlin in 1704, working at first at the apothecary shop of Christoph Schmedicke. Soon thereafter he became a traveling apothecary for the king of Prussia, Frederick I,Noretta Koertge:''Complete Dictionary of Scientific Biography'' and he continued in this capaci ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nicolas Lemery
Nicolas Lémery (or Lemery as his name appeared in his international publications) (17 November 1645 – 19 June 1715), French chemist, was born at Rouen. He was one of the first to develop theories on acid-base chemistry. Life After learning pharmacy in his native town he became a pupil of Christophe Glaser in Paris, and then went to Montpellier, where he began to lecture on chemistry. He next established a pharmacy in Paris, still continuing his lectures, but following 1683, being a Calvinist, he was obliged to retire to England. In the following year he returned to France, and turning Catholic in 1686 was able to reopen his shop and resume his lectures. He died in Paris on 19 June 1715. Lemery did not concern himself much with theoretical speculations, but holding chemistry to be a demonstrative science, confined himself to the straightforward exposition of facts and experiments. In consequence, his lecture-room was thronged with people of all sorts, anxious to hear a man w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pharmacist
A pharmacist, also known as a chemist in English in the Commonwealth of Nations, Commonwealth English, is a healthcare professional who is knowledgeable about preparation, mechanism of action, clinical usage and legislation of medications in order to dispense them safely to the public and to provide consultancy services. A pharmacist also often serves as a primary care provider in the community and offers services, such as health screenings and immunizations. Pharmacists undergo university or graduate-level education to understand the biochemical mechanisms and actions of drugs, drug uses, therapeutic roles, side effects, potential drug interactions, and monitoring parameters. In developing countries, a diploma course from approved colleges qualifies one for pharmacist role. This is mated to anatomy, physiology, and pathophysiology. Pharmacists interpret and communicate this specialized knowledge to patients, physicians, and other health care providers. Among other licensing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gothenburg
Gothenburg ( ; ) is the List of urban areas in Sweden by population, second-largest city in Sweden, after the capital Stockholm, and the fifth-largest in the Nordic countries. Situated by the Kattegat on the west coast of Sweden, it is the gubernatorial seat of Västra Götaland County, with a population of approximately 600,000 in the city proper and about 1.1 million inhabitants in Metropolitan Gothenburg, the metropolitan area. Gustavus Adolphus, King Gustavus Adolphus founded Gothenburg by royal charter in 1621 as a heavily fortified, primarily Dutch, trading colony. In addition to the generous privileges given to his Dutch allies during the ongoing Thirty Years' War, e.g. tax relaxation, he also attracted significant numbers of his German and Scottish allies to populate his only town on the western coast; this trading status was furthered by the founding of the Swedish East India Company. At a key strategic location at the mouth of the , where Scandinavia's largest dr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dominions Of Sweden
The Dominions of Sweden or ''Svenska besittningar'' ("Swedish possessions") were territories that historically came under control of the Swedish Crown, but never became fully integrated with Sweden. This generally meant that they were ruled by Governors-General under the Swedish monarch, but within certain limits retained their own established political systems, essentially their diets. Finland was not a dominion, but a land of Sweden. The dominions had no representation in the Swedish Riksdag as stipulated by the 1634 Instrument of Government paragraph 46: ''"No one, who is not living inside the separate and old borders of Sweden and Finland, have anything to say at Riksdags and other meetings..."'' Baltic Dominions Between 1561 and 1629 Sweden made conquests in the Eastern Baltic. All of them were lost in accordance with the Treaty of Nystad in 1721, which concluded the Great Northern War. Estonia Estonia placed itself under Swedish rule in 1561 to receive protecti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arsenic Acid
Arsenic acid or arsoric acid is the chemical compound with the chemical formula, formula . More descriptively written as , this colorless acid is the arsenic analogue of phosphoric acid. Arsenate and phosphate salts behave very similarly. Arsenic acid as such has not been isolated, but is only found in solution, where it is largely ionized. Its hemihydrate form () does form stable crystals. Crystalline samples dehydrate with condensation at 100 °C. Properties It is a tetrahedral species of idealized symmetry group, symmetry ''C''3v with As–O bond lengths ranging from 1.66 to 1.71 Å. Being a triprotic acid, its acidity is described by three equilibria: :, p''K''a1 = 2.19 :, p''K''a2 = 6.94 :, p''K''a3 = 11.5 These acid dissociation constant, p''K''a values are close to those for phosphoric acid. The highly basic arsenate, arsenate ion () is the product of the third ionization. Unlike phosphoric acid, arsenic acid is an oxidizer, as illustrated by its ability to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrocyanic Acid
Hydrogen cyanide (formerly known as prussic acid) is a chemical compound with the formula HCN and structural formula . It is a highly toxic and flammable liquid that boils slightly above room temperature, at . HCN is produced on an industrial scale and is a highly valued precursor to many chemical compounds ranging from polymers to pharmaceuticals. Large-scale applications are for the production of potassium cyanide and adiponitrile, used in mining and plastics, respectively. It is more toxic than solid cyanide compounds due to its volatile nature. A solution of hydrogen cyanide in water, represented as HCN( aq), is called ''hydrocyanic acid''. The salts of the cyanide anion are known as cyanides. Whether hydrogen cyanide is an organic compound or not is a topic of debate among chemists, and opinions vary from author to author. Traditionally, it is considered inorganic by a significant number of authors. Contrary to this view, it is considered organic by other authors, because ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
