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
Seasonal flows on warm Martian slopes water, most are not, and many appear at temperatures as low as . Some scientists think that under these cold conditions, a brine of iron(III) sulphate (Fe(SO)) or calcium chloride () is the most likely mode of RSL formation. Another team of scientists, using the CRISM instrument onboard MRO, reported that the evidence for hydrated salts is most consistent with the spectral absorption features of magnesium perchlorate (Mg(ClO)), magnesium chloride (MgCl(H2O)) and sodium perchlorate (). Experiments and calculations demonstrated that recurring slope lineae could be produced by the deliquescence and rehydration of hydrous chlorides and oxychlorine salts. However, under present