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Strontium is a chemical element ... This approach helps to identify the ancient migration patterns and the origin of ... Those with a personal or family history of ...
Throughout the history of chemistry, many chemical elements have been discovered. In the 19th century, Dmitri Mendeleev formulated the periodic table, a table of elements which describes their structure. Because elements have been discovered at various times and places, from antiquity through the present day, their names have derived from ...
Strontium: 1790 Adair Crawford: 1808 H. Davy Adair Crawford in 1790 found that strontianite (strontium carbonate) and witherite (barium carbonate) have different chemical properties, and suspected strontianite contained a new earth. Before him, strontianite is seen as a type of witherite. Strontium was eventually isolated electrochemically in ...
The element was eventually isolated by Sir Humphry 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. [8] In keeping with the naming of the other alkaline earths, he changed the name to strontium.
Celestine (the IMA-accepted name) [6] or celestite [1] [7] [a] is a mineral consisting of strontium sulfate (Sr S O 4). The mineral is named for its occasional delicate blue color. Celestine and the carbonate mineral strontianite are the principal sources of the element strontium, commonly used in fireworks and in various metal alloys.
The ratio 87 Sr/ 86 Sr is the parameter typically reported in geologic investigations; [4] ratios in minerals and rocks have values ranging from about 0.7 to greater than 4.0 (see rubidium–strontium dating). Because strontium has an electron configuration similar to that of calcium, it readily substitutes for calcium in minerals.
At high electron densities strontium titanate becomes superconducting below 0.35 K and was the first insulator and oxide discovered to be superconductive. [8] Strontium titanate is both much denser (specific gravity 4.88 for natural, 5.13 for synthetic) and much softer (Mohs hardness 5.5 for synthetic, 6–6.5 for natural) than diamond.
Strontium and barium have fewer applications than the lighter alkaline earth metals. Strontium carbonate is used in the manufacturing of red fireworks. [76] Pure strontium is used in the study of neurotransmitter release in neurons. [77] [78] Radioactive strontium-90 finds some use in RTGs, [79] [80] which utilize its decay heat.