Before the 19th century, no distinction was made between potassium and sodium. Sodium was first isolated by Davy in the same year by passing an electric current through molten sodium hydroxide (NaOH). When Davy heard that Berzelius and Pontin prepared calcium amalgam by electrolyzing lime in mercury, he tried it himself. Davy was successful, and discovered calcium in 1808 by electrolyzing a mixture of lime and mercuric oxide.
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Frémy therefore devised a method for producing dry hydrogen fluoride by acidifying potassium bifluoride (KHF2). Unfortunately, pure hydrogen fluoride did not pass an electric current. Frémy also tried electrolyzing molten calcium fluoride and probably produced some fluorine (since he made calcium metal at the other electrode), but he was unable to collect the gas. English chemist George Gore also tried electrolyzing dry HF and may have made small quantities of fluorine gas in 1860.
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Vemork power station in 2008. The electrolyzing plant no longer exists. The properties of heavy water had been discovered in 1932 by Harold Urey. In 1933, Leif Tronstad and Jomar Brun, the head of Norsk Hydro Rjukan, created a plan for industrial production of heavy water in Norway.
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The Hofmann voltameter is an apparatus for electrolyzing water, invented by August Wilhelm von Hofmann in 1866.von Hofmann, A. W. Introduction to Modern Chemistry: Experimental and Theoretic; Embodying Twelve Lectures Delivered in the Royal College of Chemistry, London. Walton and Maberly, London, 1866. It consists of three joined upright cylinders, usually glass.
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It can also be formed by heating sulfur hexafluoride with air to 400°. This can happen when inhaling through a lit cigarette. Or the reaction of silver difluoride with thionyl fluoride at 200 degrees. Another way to form it is by electrolyzing hydrogen fluoride with a solution of sulfur dioxide, which also made oxygen difluoride and sulfuryl fluoride.
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In 1921, Stock first prepared metallic beryllium by electrolyzing a fused mixture of sodium and beryllium fluorides. This method made beryllium available for industrial use, such as in special alloys and glasses and for making windows in X-ray tubes. He was also influential in coordination chemistry. The term "ligand" (from ligare Latin, to bind) was first used by Stock in 1916.
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In 1886, French chemist Henri Moissan, later a Nobel Prize winner, succeeded in making elemental fluorine by electrolyzing a mixture of potassium fluoride and hydrogen fluoride. Large- scale production and use of fluorine began during World War 2 as part of the Manhattan Project. Earlier in the century, the main fluorochemicals were commercialized by the DuPont company: refrigerant gases (Freon) and polytetrafluoroethylene plastic (Teflon).
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Chlorine solutions can be generated on site by electrolyzing common salt solutions. A solid form, calcium hypochlorite, releases chlorine on contact with water. Handling the solid, however, requires more routine human contact through opening bags and pouring than the use of gas cylinders or bleach, which are more easily automated. The generation of liquid sodium hypochlorite is inexpensive and also safer than the use of gas or solid chlorine.
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As an alternative, ascorbic acid can be treated with iodine in excess, followed by back titration with sodium thiosulfate using starch as an indicator. This iodometric method has been revised to exploit reaction of ascorbic acid with iodate and iodide in acid solution. Electrolyzing the solution of potassium iodide produces iodine, which reacts with ascorbic acid. The end of process is determined by potentiometric titration in a manner similar to Karl Fischer titration.
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However, because of high vapor pressure of ZnO, growth from the melt is problematic. Growth by gas transport is difficult to control, leaving the hydrothermal method as a preference. Thin films can be produced by chemical vapor deposition, metalorganic vapour phase epitaxy, electrodeposition, pulsed laser deposition, sputtering, sol-gel synthesis, atomic layer deposition, spray pyrolysis, etc. Ordinary white powdered zinc oxide can be produced in the laboratory by electrolyzing a solution of sodium bicarbonate with a zinc anode.
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SOECs have possible application in fuel production, carbon dioxide recycling, and chemicals synthesis. In addition to the production of hydrogen and oxygen, an SOEC could be used to create syngas by electrolyzing water vapor and carbon dioxide.Ceramatec Solid Oxide Co-Electrolysis Cell This conversion could be useful for energy generation and energy storage applications. MIT will test the method on the Perseverance rover as a means to produce oxygen for both human sustenance and liquid oxygen rocket propellant.
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Preparation of copper(II) sulfate by electrolyzing sulfuric acid, using copper electrodes Copper sulfate is produced industrially by treating copper metal with hot concentrated sulfuric acid or its oxides with dilute sulfuric acid. For laboratory use, copper sulfate is usually purchased. Copper sulfate can also be produced by slowly leaching low grade copper ore in air; bacteria may be used to hasten the process. Commercial copper sulfate is usually about 98% pure copper sulfate, and may contain traces of water.
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He warned of the presence of civil housing, and argued that bombing was not even guaranteed to succeed, given that the heavy water facility was located in the armoured basement of the electrolyzing plant. The first attempt to take out the facility, in November 1942, had consisted of British personnel using gliders to land near Vemork. The operation, codenamed Freshman, was a catastrophe, as all units except for one towing aircraft perished, either due to crash landings or in German captivity. Tronstad then organized the next attempt.
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Supply of oxygen and hydrogen by electrolyzing water in space plays an important role in meeting NASA's needs and goals for future space missions. On-board generation of oxygen was expected to reduce the annual resupply requirement for the Space Station by approximately . Other payloads aboard were the National Institutes of Health- Cells-4 (NIH-C4) experiment that investigates bone loss during space flight; the Biological Research in Canister-6 (BRIC-6) that studies the gravity- sensing mechanism within mammalian cells. Also flying were two commercial experiments.
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The energy source is currently electricity from photovoltaic plants or hydroelectric power stations that temporarily fluctuates heavily and is not needed on the power grid. It is initially converted into hydrogen or methane by electrolyzing water (power-to-gas concept). At the same time, a third platform commences operations: ehub (Energy Hub), which acts as a kind of nerve center to control and coordinate energy flows between NEST and “move” with their various energy users and sources. ehub should therefore guarantee an optimized energy supply, especially using heavily fluctuating energy sources such as solar and wind power.
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Soft robots, particularly those designed to imitate life, often must experience cyclic loading in order to move or do the tasks for which they were designed. For example, in the case of the lamprey- or cuttlefish-like robot described above, motion would require electrolyzing water and igniting gas, causing a rapid expansion to propel the robot forward. This repetitive and explosive expansion and contraction would create an environment of intense cyclic loading on the chosen polymeric material. A robot underwater and/or on Europa would be nearly impossible to patch up or replace, so care would need to be taken to choose a material and design that minimizes initiation and propagation of fatigue-cracks. In particular, one should choose a material with a fatigue limit, or a stress-amplitude frequency above which the polymer’s fatigue response is no longer dependent on the frequency.
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