Davy, Humphry elements named

Calcium was first recognized as an element in 1808 by Humphry Davy, and the name was given after the Latin for lime calx. Several isotopes of ealcium are known. The stable isotopes are, in order of decreasing natural abundance, " Ca (96.94%), " Ca (2.1%), Ca (0.64%), and Ca (0.145%). Ca is the only isotope with a nuclear spin (/ = ) different from zero, whieh makes it amenable to NMR studies. Ca is a radioactive isotope of some importance ()S decay 8.8 min half life). It has been used in studies of calcium localization and transport in biological systems. 

The spectacular success (in 1807) of Humphry Davy, then aged 29 y, in isolating metallic potassium by electrolysis of molten caustic potash (KOH) is too well known to need repeating in detail." Globules of molten sodium were similarly prepared by him a few days later from molten caustic soda. Earlier experiments with aqueous solutions had been unsuccessful because of the great reactivity of these new elements. The names chosen by Davy reflect the sources of the elements. 

Magnesium (Mg, [Ne]3.v2), name, and symbol, from the Greek word Magnesia a city of Thessaly. Recognized as an element (1755) by Joseph Black, isolated (1808) by Humphry Davy. 

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. 

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. 

The mineral petalite was mined as an ore in Sweden. In 1817 Johan August Arfwedson (1792—1841) analyTed this new mineral. After identifying several compounds in the ore, he realized there was a small percentage of the ore that could not be identified. After applying more analytical procedures, he determined it was a new alkali. It turned out that petalite contains hthium aluminum silicate, LiAllSi O lj. In 1818 the first lithium metal was prepared independently by two scientists, Sir Humphry Davy (1778—1892) and W.T. Brande (1788—1866). Lithium was discovered at a time in the early nineteenth century when numerous new elements were discovered and identified by other scientists. Many of these newly named elements were predicted by the use of the periodic table of the chemical elements. 

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. 

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. 

Similar to the history of many other elements, iodine s discovery was serendipitous in the sense that no one was looking for it specifically. In 1811 Bernard Courtois (1777—1838), a French chemist, attempted to remove sodium and potassium compounds from the ash of burned seaweed in order to make gunpowder. After removing these chemicals from the ash, he added sulfuric acid (H SO j) to the remaining ash. However, he mistakenly added too much acid, which produced a violet-colored vapor cloud that erupted from the mixture. This violet vapor condensed on all the metallic objects in the room, leaving a layer of sohd black iodine crystals. Sir Humphry Davy (1778—1829) confirmed this discovery of a new element and named it iodine after the Greek word iodes, which means violet, but it was Courtois who was given credit for the discovery of iodine. 

Potassium was first isolated as a free metal in 1807 by Sir Humphry Davy. It was the first alkali metal to be discovered, produced by electrolysis of potassium carbonate (potash). The element was earlier called Kalium, derived from the Arabic word qili, meaning grass wort, the ash of which was a source of potash. The element derived its symbol K from Kalium. The English name potassium came from potash (pot ash), the carbonate salt of the metal. 

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. 

Some elements have several different forms. In the case of carbon, charcoal was the only recognized form until early in the nineteenth century. The name carbon actually comes from the Eatin word carbo, meaning charcoal. In 1812, Sir Humphry Davy used sunlight to set a diamond on fire. This demonstration, combined with his scientific explanation, proved that diamonds were made of pure carbon. Around the same time, Davy also showed that coal was another form of carbon. Graphite, which is the lead in pencils, is... 

Aluminium was first named (although not isolated) by Sir Humphry Davy, who originally called it alumium (1808) because it was found in alum, a name that had been extant since at least the 14th century. He later called it aluminum (1812), but others soon changed it to aluminium, in order to harmonize it with the many other elements whose... 

Calcium was named by Humphry Davy after the material from which it was produced, calx, the Latin for limestone. Davy isolated calcium metal in 1808 by electrolysis. Although calcium never occurs in elemental form, calcium compounds are widely found in nature, particularly in limestone and gypsum. Calcium metal is used in the production and purification of other metals, while calcium compounds have thousands of uses, including chemical production, plaster, and Portland cement. 

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. 

In elemental form, calcium is a relatively soft, silvery metal. Like other alkaline earths, it is too reactive to be found as a free element in nature. It was not until 1808 that Sir Humphry Davy isolated it by doing electrolysis on a mixture of lime (CaO) and mercuric oxide. Calcium s name comes from the Latin word calx, which means hme, a substance used since ancient Roman times in various ways, including as plasters for construction. 

Sodium is a soft, silvery alkali metal and reacts vigorously with water to generate hydrogen gas. The word sodium is derived from sodanum (a Medieval Latin name for a headache remedy), and natrium (Latin for soda ) is the origin of the element s symbol. Humphry Davy isolated the element in 1807 via the electrolysis of caustic soda, NaOH. Currently, sodium metal is obtained from the electrolysis of a molten mixture of sodium chloride and... 

Although calcium (Ca) metal was discovered in 1808 independently by Sir Humphry Davy and Berzelius and Pontin, the pure metal was first produced by Moissan in 1898. The name of calcium is derived from the Latin calx , meaning lime. Calcium constitutes 3.63% of the Earth s crust, and is the fifth most abundant element in the environment as well as in the human body. Due to its reactivity, it only occurs naturally in the form of its compounds for example, various magmatic rocks, carbonate (limestone), and sulfate. Calcium is indispensable for life, namely for the maintenance of structure and metabolism. Its structural roles include that of coral, the secreted shells of mollusks and, in particular, the internal skeleton of vertebrates (Hluchan and Pomerantz 2002). 

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