Strontium does not occur as the free element. Strontium is softer than calcium and decomposes water more vigorously. Freshly cut strontium has a silvery appearance, but rapidly turns a yellowish color with the formation of the oxide. The finely divided metal ignites spontaneously in air. Volatile strontium salts impart an excellent crimson color to flames, and these salts are used inpyrotechnics.
The result of adding different metal salts to a burning reaction mixture of potassium chlorate and sucrose. The red color originates from strontium sulphate. The orange/yellow color originates from sodium chloride. The green color originates from barium chlorate and the blue color originates from copper (I) chloride. The lilac color that should be evident from the potassium chlorate is washedout by the other colors, all of which are more intense (only to be demonstrated by a professionally qualified chemist following a legally satisfactory hazard assessment). Improperly done, this reaction is dangerous!
Strontium is named after the Scottish village of Strontian (Gaelic Sron an t-Sithein), having been discovered in the ores taken from the lead mines. In 1790, Adair Crawford, aphysician engaged in the preparation of barium, recognized that the Strontian ores exhibited different properties to those normally seen with other "heavy spars" sources. This allowed him to conclude "... it is probable indeed, that the scotch mineral is a new species of earth which has not hitherto been sufficiently examined". The new mineral was named strontites in 1793 by Thomas Charles Hope, aprofessor of chemistry at the University of Glasgow. He confirmed the earlier work of Crawford and recounted: " ... Considering it a peculiar earth I thought it necessary to give it an name. I have called it Strontites, from the place it was found; a mode of derivation in my opinion, fully as proper as any quality it may possess, which is the present fashion". The element was eventually isolated by SirHumphry Davy in 1808 by the electrolysis of a mixture containing strontium chloride and mercuric oxide, and announced by him in a lecture to the Royal Society on 30 June 1808. In keeping with the naming of the other alkaline earths, he changed the name to strontium.
The first large-scale application of strontium was in the production of sugar from sugar beet. Although a crystallization processusing strontium hydroxide was patented by Augustin-Pierre Dubrunfaut in 1849 the large-scale introduction came with the improvement of the process in the early 1870s. The German sugar industry used the process well into the 19th century. Prior to World War I the beet sugar industry used 100,000 to 150,000 tons of strontium hydroxide for this process per year. The strontium hydroxide was recycled inthe process, but the demand to substitute losses during production was high enough to create a significant demand initiating mining of strontianite in the Münsterland. The mining of strontianite in Germany ended when mining of the celestite deposits in Gloucestershire started. These mines supplied most of the world strontium supply from 1884 to 1941.
Barium is a metallic element, soft, and whenpure is silvery white like lead. The metal oxidizes very easily and it reacts with water or alcohol. Barium is one of the alkaline-earth metals. Small amounts of barium compounds are used in paints and glasses.
The result of adding different metal salts to a burning reaction mixture of potassium chlorate and sucrose. The red color originates from strontium sulphate. The orange/yellow colororiginates from sodium chloride. The green color originates from barium chlorate and the blue color originates from copper (I) chloride. The lilac color that should be evident from the potassium chlorate is washed out by the other colors, all of which are more intense (only to be demonstrated by a professionally qualified chemist following a legally satisfactory hazard assessment). Improperly done,...
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