Davy, Humphry boron

Sodium borohydride is marketed in powdered or pellet form, and in solution, for use in fuel cells. Boron nitride can withstand temperatures of up to 650°C (1,202°E) when subjected to high pressures and temperatures, it forms cubic crystals whose hardness rivals that of diamond. Boron carbide, produced by reacting coke and boric acid at 2,600°C (4,712°E), is a highly refractory material and one of the hardest substances known. It has both abrasive and abrasion-resistant applications, and is used in nuclear shielding, see ALSO Davy, Humphry Gay-Lussac, Joseph-Louis Nuclear Chemistry. 

Ar. Buraq, Pers. Burah) Boron compounds have been known for thousands of years, but the element was not discovered until 1808 by Sir Humphry Davy and by Gay-Lussac and Thenard. 

Obtained by Sir Humphry Davy (1778-1829) by reduction of boronic acid (H3BO3) with potassium. 

Boron (Buraq in Arabic/Burah in Persian, which is the word for white, the color being attributed to borax (sodium tetraborate, Na2B4O7.10H2O)) was discovered in 1808 independently by the British Chemist, Sir Humphry Davy, and two French chemists, Joseph Louis Gay-Lussac and Loius Jacques Thenard.1 They isolated boron in 50% purity by the reduction of boric acid with sodium or magnesium. The Swedish chemist Jons Jakob Berzilius identified boron as an element in 1824. The first pine sample of boron was produced by the American chemist William Weintraub in 1909. Boron does not appear in nature in elemental form, but is found in its compounded... 

Boron (B, [He]2.v22p1), name and symbol from the Persian word burah and the Arabic word buraq (borax). The suffix-on was added because of the similarity to carbon. Discovered (1808) by J.-L. Gay-Lussac and L.J. Thenard in France and Humphry Davy in England. 

Boron - the atomic number is 5 and the chemical symbol is B. The name derives from the Arabic buraq for white . Although its compounds were known for thousands of years, it was not isolated until 1808 when the French chemists Louis-Joseph Gay-Lussac and Louis-Jacques Thenard obtained boron in an impure state and the English chemist, Humphry Davy, prepared pure boron by electrolysis. 

Boron B 1808 (London England and Paris, France) Sir Humphry Davy (British) and Joseph Gay-Lussac, Louis Thenard (both French) 175... 

Sir Humphry Davy, 1778—1829. English chemist and physicist. One of the founders of electrochemistry. Inventor of die safety lamp for miners. He was the first to isolate potassium, sodium, calcium, barium, strontium, and magnesium. Davy in England and Gay-Lussac and Thenard in France, working independently, were die first to isolate boron. 

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. 

In 1808, English chemist Humphry Davy (1778—1829) had just learned how to isolate the most active metals, such as sodium and potassium. He was also working on a method to remove boron from its compounds. 

Boron occurs in nature as part of oxygenated compounds, or borates, that have been known since ancient times for their use in glass and metal production. In 1808 Joseph-Lotiis Gay-Lussac and Louis Jacques Thenard of France and Humphry Davy of England discovered the element boron almost concurrently. Another century passed before boron was successfully isolated in pure form. Elemental boron in its amorphous form is a dark brown powder it is a yellowish-brown, hard, brittle solid in its monoclinic crystalline form. It melts at 2,300°C (4,172°E). Boron is unreactive to oxygen, water, acids, and alkalis. Boron compotmds burn yellow-green during the flame test. 

Boron — (Ar. Buraq, Pers. Burah), B at. wt. 10.811(7) at. no. 5 m.p. 2075°C b.p. 4000°C sp. gr. of crystals 2.34, of amorphous variety 2.37 valence 3. Boron compounds have been known for thousands of years, but the element was not discovered until 1808 by Sir Humphry Davy and by Gay-Lussac and Thenard. The element is not found free in nature, but occurs as orthoboric acid usually in certain volcanic spring waters and as borates in borax and colemanite. Ulexite, another boron mineral, is interesting as it is nature s own version of fiber optics. Important sources of boron are the ores rasorite (kern-ite) and tincal (borax ore). Both of these ores are found in the Mojave Desert. Tincal is the most important source of boron from the Mojave. Extensive borax deposits are also found in Turkey. Boron exists naturally as 19.9% B isotope and 80.1% B isotope. Ten other isotopes of boron are known. High-purity crystalline boron may be prepared by the vapor phase reduction of boron trichloride or tribromide with hydrogen on... 

Louis-Joseph Gay-Lussac and Louis-Jacques Thenard in Paris, and Sir Humphry Davy in London. Boron is difficult to isolate, and when the purest form was isolated by E. Weintraub in 1909, it was found to have wildly different properties of the impure boron samples synthesized prior to 1909. 

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. 

History. Boron was first successfully prepared by the French chemists Joseph Gay-Lussac and Baron Louis Thenard in 1808 and independently by the British chemist Sir Humphry Davy. During and after World War 11, research escalated in the boron field, especially with advances in ceramic materials. 

English chemist Humphry Davy discovers the elements barium and calcium. French chemist Joseph-Louis Gay-Lussac proposes Gay-Lussac s law gases combine among themselves in very simple proportions. English chemist John Dalton publishes A New System of Chemical Philosophy, in which he formulates the atomic weight theory. Davy, Gay-Lussac, and French chemist Louis-Jacques Thenard isolate the element boron. Polish chemist Jedrzej Sniadecki discovers the element ruthenium. 

Boron 1808 Humphry Davy (U.K.) Joseph-Louis Gay-Lussac (France) and Louis-Jacques Thenard (France)... 

The element boron was discovered in 1808. A gray powder of boron was formed in the reaction between potassium metal and boric add. This discovery was made by J.-L. Gay-Lussac and L. J. Thenard in Paris and almost simultaneously by Sir Humphry Davy in London. That the name for the new element should contain the syllable bor was natural due to its origin in borax. Davy saw similarities between the new element and carbon, and found it logical to use the name boron. It also became the name of the element in the English language. 

Boron was known to the ancients in the form of borax, which was used for various types of glass. Boron is almost always found directly bound to oxygen and is difficult to prepare in pure form. In 1808 the ebullient chemist Sir Humphry Davy, whom we encountered as the discoverer of potassium and sodium (p. 324) as well as magnesium, calcium, strontium, and barium (p. 355), was just barely beaten (by 9 days) to the discovery of boron by the French chemists Joseph Louis Gay-Lussac and Louis Jacques Thenard. Yes, this is the same Gay-Lussac who proved (in 1802) that the volume of a gas is directly proportional to the temperature. (Jacques Charles, a French physicist, actually formulated this relationship some 15 years earlier, but... 

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