Bis(tri-tert-butylcyclopentadienyl) Strontium

See more Strontium products. Strontium (atomic symbol: Sr, atomic number: 38) is a Block S, Group 2, Period 5 element with an atomic weight of 87.62 . The number of electrons in each of Strontium's shells is [2, 8, 18, 8, 2] and its electron configuration is [Kr] 5s². The strontium atom has a radius of 215 pm and a Van der Waals radius of 249 pm. Strontium was discovered by William Cruickshank in 1787 and first isolated by Humphry Davy in 1808. In its elemental form, strontium is a soft, silvery white metallic solid that quickly turns yellow when exposed to air. Cathode ray tubes in televisions are made of strontium, which are becoming increasingly displaced by other display technologies pyrotechnics and fireworks employ strontium salts to achieve a bright red color. Radioactive isotopes of strontium have been used in radioisotope thermoelectric generators (RTGs) and for certain cancer treatments. In nature, most strontium is found in celestite (as strontium sulfate) and strontianite (as strontium carbonate). Strontium was named after the Scottish town where it was discovered.