What is strontium?

   Strontium is a metallic element, with atomic number 38, atomic weight 87.6, and symbol Sr. It belongs to the group of elements called the alkaline earth metals, the other members of which are calcium, barium, and radium. Metallic strontium was first isolated by the English chemist Sir Humphry Davy in 1808; the oxide had been known as early as 1790. The element is never found in the native state, occurring chiefly as strontianite, SrCO₃, and celestite, SrSO₄. Strontium is 15th among the elements in order of abundance, and is widely dis-tributed in small quantities, the greatest amounts being mined in England and Scotland. Strontium is a brass-yellow metal with a specific gravity of 2.6. It melts at 800 °C. (1472 °F.) and has a boiling point of 1150 °C. (2102 °F.). It is malleable and ductile. oxidizes readily upon exposure to air, and reacts with water to produce strontium hydroxide and hydrogen gas. Like the other alkaline earth metals, it is prepared by transforming the carbonate or sulfate into the chloride which, upon hydrolysis, yields the metal. Because it emits a brilliant red color when burned in air, strontium is used in the manufacture of fireworks and railroad flares. Strontia (strontium oxide) SrO, is used in recovering sugar from beet-sugar molasses.