Magnesium sulfide reacts with oxygen to form the corresponding sulfate, magnesium sulfate. MgS reacts with water to give hydrogen sulfide and magnesium hydroxide. In the BOS steelmaking process, sulfur is the first element to be removed. Sulfur is removed from the impure blast furnace iron by the addition of several hundred kilograms of magnesium powder by a lance. Magnesium sulfide is formed, which then floats on the molten iron and is removed. MgS is a wide band-gap direct semiconductor of interest as a blue-green emitter, a property that has been known since the early 1900s. The wide-band gap property also allows the
Magnesium hydroxide formation of expansive brucite. This reaction, one of the two main alkali-aggregate reaction (AAR) is also known as alkali-carbonate reaction. Magnesium hydroxide Magnesium hydroxide is the inorganic compound with the chemical formula Mg(OH). It occurs in nature as the mineral brucite. It is a white solid with low solubility in water (). Magnesium hydroxide is a common component of antacids, such as milk of magnesia, as well as laxatives. Combining a solution of many magnesium salts with alkaline water induces precipitation of solid Mg(OH): On a commercial scale, Mg(OH) is produced by treating seawater with lime (Ca(OH)). 600m of seawater