Davy, Humphry strontium

William Cruickshank in 1787 and Adair Crawford in 1790 independently detected strontium in the mineral strontianite, small quantities of which are associated with calcium and barium minerals. They determined that the strontianite was an entirely new mineral and was different from baryta and other barium minerals known at the time. In 1808, Sir Humphry Davy isolated strontium by electrolysis of a mixture of moist strontium hydroxide or chloride with mercuric oxide, using a mercury cathode. The element was named after the town Strontian in Scotland where the mineral strontianite was found. 

There are four stable isotopes of strontium that are found naturally. In addition there are about twenty radioactive isotopes, including strontium-90, a deadly by-product of nuclear-bomb detonations. The natural forms of strontium are relatively nontoxic. Similar to calcium both physically and chemically, elemental strontium is a soft, shiny metal. Like calcium and other alkaline earth metals, it is easily oxidized and thus not found naturally in its free elemental state. Instead, it almost always is found in the + 2 oxidation state, forming such compounds as strontium oxide (SrO), strontium sulfate (SrS04, from the mineral celestite), strontium carbonate (SrCOj, from the mineral strontianite), and strontium chloride (SrC. Strontium nitrate, Sr(N03)2, is used to produce the brilliant red color seen in some fireworks and signal flares and is also used in making tracer bullets that can be seen when fired at night. Other strontium compounds are sometimes used in the manufacture of special glasses. Yet overall, strontium is not a very important element industrially or commercially, see ALSO Davy, Humphry... 

Strontium - the atomic number is 38 and the chemical symbol is Sr. The name derives from Strontian, a town in Scotland . The mineral strontianite is found in mines in Strontian. The element was discovered by the Scottish chemist and physician Thomas Charles Hope in 1792 observing the brilliant red flame color of strontium. It was first isolated by the English chemist Humphry Davy in 1808. 

In 1787 William Cruikshank (1745-1795) isolated, but did not identify, strontium from the mineral strontianite he examined. In 1790 Dr. Adair Crawford (1748—1794), an Irish chemist, discovered strontium by accident as he was examining barium chloride. He found a substance other than what he expected and considered it a new mineral. He named the new element strontium and its mineral strontianite after a village in Scotland. In 1808 Sir Humphry Davy treated the ore with hydrochloric acid, which produced strontium chloride. He then mixed mercury oxide with the strontium chloride to form an amalgam alloy of the two metals that collected at the cathode of his electrolysis apparatus. He heated the resulting substance to vaporize the mercury, leaving the strontium metal as a deposit. 

Strontium Sr 1790 (Edinburgh, Scotland) 1808 (London, England) Adair Crawford (Irish) Sir Humphry Davy (British) 76... 

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 isolated the metal in 1808 by the method he had used for calcium and barium (5, 3). In 1924 P. S. Danner of the University of California allowed the oxides of barium and strontium to react with magnesium or aluminum and, upon distilling, obtained both barium and strontium in a high state of purity. His method was a refinement of the one previously used by A. Guntz (33, 34). 

Barium was first isolated in 1808 by English chemist Sir Humphry Davy (1778-1829). In 1807 and 1808, Davy also discovered five other new elements sodium, potassium, strontium, calcium, and magnesium. All... 

The existence of strontium was first recognized in 1790 by Irish physician Adair Crawford (1748—1795). However, the element was not prepared in pure form until nearly 20 years later by English chemist Humphry Davy (1778—1829). 

English chemist Sir Humphry Davy isolates a number of elements in a pure form for the first time, including potassium, sodium, magnesium, barium, calcium, and strontium. 

Strontium Sr 38 87.62 1808 Sir Humphry Davy (GB) Strontian, Scotland, derived from mineral strontionite... 

Sir Humphry Davy was an English scientist, who discovered metals such as potassium, sodium, barium, strontium, calcium and magnesium. His most famous invention was a safety lamp for use in coal mines where the highly inflammable gas, methane, is often found. Davy first proposed the name for the element with the symbol Al and called it alumium, but he changed his mind, a few years later, and called it aluminum. Many British users disliked this name, however, because it didn t conform with the ium ending given in the names of metals and adopted the name aluminium. Americans still prefer aluminum, which is why you will see this spelling in their textbooks. 

In 1790 Adair Crawford and William Cruikshank first detected non-radioactive strontium in the mineral strontianite in Scotland. Metallic strontium was isolated in 1808 by Sir Humphry Davy. Radioactive Sr-90, like many other radionuclides, was discovered in the 1940s in nuclear experiments connected to the development of the atomic bomb. 

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. 

A Humphry Davy was one of the first scientists to discover new elements using batteries. He discovered six elements (sodium, potassium, magnesium, calcium, strontium, and barium) this way. 

The element was first identified by the British chemist Adair Crawford in 1790 (Edinburgh, Scotland). Actually, he recognized a new heavy mineral (later named strontianite) that differed from the heavy barium sulfate barite. Later, in 1809, the metal was first isolated by the British chemist Sir Humphry Davy by performing molten-salt electrolysis of strontium chloride. 

The early chemists gave the name earth to many nonmetallic substances. Magnesium oxide and calcium oxide were found to have an alkaline reaction, and hence were called the alkaline earths. The metals themselves (magnesium, calcium, strontium, and barium) were isolated in 1808 by Humphry Davy. Beryllium was discovered in the mineral beryl (BesAbSigOis) in 1798 and was isolated in 1828. 

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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