Davy, Humphry chlorine

Having been led to repeat this experiment, from some objections made by the last mentioned gentleman to the theory of my brother. Sir HUMPHRY Davy, concerning chlorine, I was surprised at witnessing a different result. 

English chemist Humphry Davy proves chlorine to be an... 

Carl Wilhelm Scheele (1742-1786) discovered chlorine in the reaction of hydrochloric acid with manganese dioxide (pyrolusite or brownstone ore). Recognized as an element by Sir Humphry Davy (1778-1829). 

Chlorine - the atomic number is 17 and the chemical symbol is Cl. The name derives from the Greek chlooros for pale green or greenish yellow color of the element. It was discovered by the Swedish pharmacist and chemist Carl-Wilhelm Scheele in 1774. In 1810, the English chemist Humphry Davy proved it was an element and gave it the name chlorine. 

Sometime later. Sir Humphry Davy believed that when acid reacted with a metal, the acid was the source of this unknown gas. This belief was at odds with the positions of most of the chemists of the day who believed that the source of the gas was the metals themselves—not the acid. In 1810 Davy declared that the new element was chlorine. He is generally recognized as the discoverer of chlorine because he correctly identifled it as a new element. Some scientists of the day claimed that Davy believed the new element was a compound of oxygen and thus misdiagnosed the new element. Most accepted his identiflcation of the new element and used the name proposed by Scheele. 

Chlorine Cl 1774 (Uppsala, Sweden) 1810 (London, England) Carl Wilhelm Scheele (Swedish) Sir Humphry Davy (British) 248... 

Sir Humphry Davy, 1778-1829. British chemist who isolated the alkali and alkaline earth metals and boron, and proved that chlorine is an element. Gay-Lussac and Thenard isolated boron independently at about the same time. 

Clement believed iodine to be an element similar to chlorine 12), and showed it, first to J.-A.-C. Chaptal and A.-M. Ampere, and later to Sir Humphry Davy. The proof of its elementary nature was given independently by Davy in England and by Gay-Lussac in France. Davy showed that iodine vapor is not decomposed by a carbon filament heated red-hot by a voltaic current (12, 46). In his classical research, the results of which were published in 1814, Gay-Lussac prepared hydrogen... 

By the action of marine acid on the black oxide of manganese, Scheele obtained chlorine gas and described its principal characteristic properties. He called it dephlo-gisticated marine acid. The name was reasonable from his point of view, since inflammable air (hydrogen) was conceived to be chiefly phlogiston and the above action deprived marine acid of its hydrogen. Chlorine was not conceived to be elementary in its nature even by Lavoisier Sir Humphry Davy, in 1810, was the discoverer of its elementary nature, and he it was who suggested the name chlorine. ... 

In 1800. William Nicholson and Anthony Carlisle decomposed water into hydrogen and oxygen by an electric current supplied by a voltaic pile. Whereas Volta had pruduced electricity from chemical action these experimenters reversed the process and utilized electricity to produce chemical changes. In 1807. Sir Humphry Davy discovered two new elements, potassium and sodium, by the electrolysis of ihe respective solid hydroxides, utilizing a voltaic pile as the source of electric power. These electrolytic processes were the forerunners of the many industrial electrolytic processes used today to obtain aluminum, chlorine, hydrogen, or oxygen, for example, or in die electroplating of metals such as silver or chromium. 

Sir Humphry Davy discovery of chlorine hydrate 1823 - Michael Faraday formula of chlorine hydrate 1841 - C. Schafhautl study of graphite intercalates 1849 - F. Wohler /Lquinol H2S clathrate 1891 - Villiers and Hebd cyclodextrin inclusion compounds... 

In one sense, the story of the chlorinated insecticides begins in 1774, since in that year the Swedish apothecary Karl Wilhelm Scheele discovered chlorine Michael Faraday, who was born in 1791 first assisted Sir Humphry Davy and later succeeded him as Professor of Chemistry at the Royal Institution in London In the Philosophical Transactions of 1825 Faraday reported that benzene reacted with chlorine in sunlight to give a "solid body" and dense, viscous fluid, which was undoubtedly the first sample of technical BHC. During the next 87 years several investigations established its constitution to be C/.H/.C1, and showed that it contained a- and 3-isomers and afforded trichlorobenzenes when treated with alkali In 1912, the Belgian chemist Van der Linden... 

Chlorine bleach is developed by Claude Louis BerthoUet in France Alessandro Volta makes a Copper/Zinc acid battery Humphry Davy invents a safety lamp that is used in coal mines without triggering an explosion... 

The hydrate of chlorine is of special interest as the solid phase originally thought to be solid chlorine but shown (in 1811) by Humphry Davy to contain water. It was later given the formula CI2. 10 H2O by Michael Faraday. The unit cell of this (cubic) structure (a 12 A) contains 46 H2O which form a framework (Fig. 15.6) in which there are 2 dodecahedral voids and 6 rather larger ones (14-hedra). If all... 

VI. On a gaseous Compound of carbonic Oxide and Chlorine. By John Davy, Esq. Communicated by Sir Humphry Davy, Knt. LL.D. Sec. R.S. 

Synthesis and Reactivity Chlorine was first prepared by the Swedish chemist K.W. Scheele in 1774 using the reaction of manganese dioxide with hydrochloric acid. Erroneously, he thought that it was a compound of oxygen, and ultimately it was named and identified as an element by Sir Humphry Davy in 1810. The reaction of hydrochloric acid with potassium permanganate provides a second convenient route to small quantities of chlorine. 

Once in Paris, Sir Humphry Davy was presented with a sample of a newly isolated, dark-gray substance by the physicist Andre Marie Ampere (Sacks, 2001, chapter 11). Some well-known French chemists had already done some preliminary work on this material Courtois had isolated it from the ashes of a sea-weed Desormes and Clement had hypothesized it might be an element with properties similar to chlorine, which was an substance everyone knew Davy had established as an element. Now it was time for Davy to have a go. In rapid response to the challenge and with great curiosity, Davy set up his portable chemistry laboratory in his Parisian hotel room (Klopfer, 1969, p. 89). He simply had to solve the mystery residing in Airpere s gift (J. Davy, 2001). 

Davy, Sir Humphry (i778-i829) British chemist, who studied gases at the Pneumatic Institute in Bristol, where he discovered the anaesthetic properties of dinitrogen oxide (nitrous oxide). He moved to the Royal Institution, London, in 1801 and five years later isolated potassium and sodium by electrolysis. He also prepared barium, boron, calcium, and strontium as well as proving that chlorine and iodine are elements. In 1816 he invented the Davy lamp. 

Faraday, Michael (1791-1867) British chemist and physicist, who received little formal education. He started to experiment on electricity and in 1812 attended lectures by Sir Humphry Davy at the Royal Institution a year later he became Dav/s assistant He remained at the Institution until 1861. Faraday s chemical discoveries include the liquefaction of chlorine (1823) and benzene (1825) as well as the laws of electrolysis [see Faraday s laws). He is probably best remembered for his work in physics in 1821 he demonstrated electromagnetic rotation (the principle of the electric motor) and discovered electromagnetic induction (the principle of the dynamo). In 1845 he discovered the Faraday effect. 

Mr. Faraday was completely at a loss to explain the occurrence, and proceeded to repeat the experiment with a view to its elucidation. I was unable, however, to remain and witness the result. Upon mentioning the circumstance to Sir Humphry Davy after dinner, he appeared much surprised and after a few moments of apparent abstraction, he said I shall enquire about this experiment to-morrow. Early the next morning, I received from Mr. Faraday the following laconic note Dear Sir, The oil you noticed yesterday turns out to be liquid chlorine. Yours faithfully, M. Faraday. ... 

In 1812 Berzelius was invited by Berthollet to visit Paris but war broke out between France and Sweden, so he went instead to England, where he visited Davy. He gives an amusing account of his reception. He says Davy took a criticism of his chlorine theory seriously. The two corresponded from 1808 till 1813, when a criticism of Davy s Elements of Chemical Philosophy put an end to the friendship. Berzelius had Davy s letters bound and wrote on the flyleaf Humphry Davy, Pres. Roy. Soc. Le plus grand chimiste de son sifecle. Berzelius was much impressed by Alexander Marcet s experimental lectures... 

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