About the Book
Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Pages: 38. Chapters: Almagate, Almasilate, Aluminium magnesium boride, Calcium magnesium acetate, Dimagnesium phosphate, Hauser base, Low valent magnesium compounds, Magaldrate, Magnesium aluminide, Magnesium aspartate, Magnesium benzoate, Magnesium bromide, Magnesium carbonate, Magnesium chloride, Magnesium citrate, Magnesium diboride, Magnesium diglutamate, Magnesium diuranate, Magnesium fluoride, Magnesium gluconate, Magnesium hydride, Magnesium hydroxide, Magnesium iodide, Magnesium iron hexahydride, Magnesium L-threonate, Magnesium lactate, Magnesium laureth sulfate, Magnesium levulinate, Magnesium malate, Magnesium nitrate, Magnesium nitride, Magnesium orotate, Magnesium oxide, Magnesium perchlorate, Magnesium peroxide, Magnesium phosphate tribasic, Magnesium pidolate, Magnesium polonide, Magnesium salicylate, Magnesium silicide, Magnesium stearate, Magnesium sulfate, Magnesium sulfide, Magnesium sulfite, Magnesium trisilicate, Monomagnesium phosphate, Reactive magnesia, Sorel cement, Trimagnesium citrate. Excerpt: Magnesium chloride is the name for the chemical compounds with the formulas MgCl2 and its various hydrates MgCl2(H2O)x. These salts are typical ionic halides, being highly soluble in water. The hydrated magnesium chloride can be extracted from brine or sea water. In North America, magnesium chloride is produced primarily from Great Salt Lake brine. It is extracted in a similar process from the Dead Sea in Israel. Magnesium chloride as the natural mineral bischofite is also extracted (via solution mining) out of ancient seabeds; for example, the Zechstein seabed in northwest Europe. Some magnesium chloride is made from solar evaporation of seawater. Anhydrous magnesium chloride is the principal precursor to magnesium metal, which is produced on a large scale. Hydrated magnesium chloride is the form most readily available. MgCl2 crystallizes in the cadmium chloride motif, which features octahedral Mg. A variety of hydrates are known with the formula MgCl2(H2O)x, and each loses water with increasing temperature: x = 12 ( 16.4 C), 8 ( 3.4 C), 6 (116.7 C), 4 (181 C), 2 (ca. 300 C). In the hexahydrate, the Mg remains octahedral, but is coordinated to six water ligands. The thermal dehydration of the hydrates MgCl2(H2O)x (x = 6, 12) does not occur straightforwardly. As suggested by the existence of some hydrates, anhydrous MgCl2 is a Lewis acid, although a very weak one. In the Dow process, magnesium chloride is regenerated from magnesium hydroxide using hydrochloric acid: Mg(OH)2(s) + 2 HCl MgCl2(aq) + 2 H2O(l)It can also be prepared from magnesium carbonate by a similar reaction. In most of its derivatives, MgCl2 forms octahedral complexes. Derivatives with tetrahedral Mg are less common. Examples include salts of (tetraethylammonium)2MgCl4 and adducts such as MgCl(TMEDA). Magnesium chloride serves as precursor to other magnesium compounds, for example by precipitation: MgCl2(aq) + Ca(OH)2(aq) Mg(OH)2(s) + CaCl2(aq)It can be electrolysed to give magnesium metal:
