Hard water boiling. When this is the case, it is usually caused by the presence of calcium sulphate/calcium chloride and/or magnesium sulphate/magnesium chloride in the water, which do not precipitate out as the temperature increases. Ions causing permanent hardness of water can be removed using a water softener, or ion exchange column. Total Permanent Hardness = Permanent Calcium Hardness + Permanent Magnesium Hardness With hard water, soap solutions form a white precipitate (soap scum) instead of producing lather, because the 2+ ions destroy the surfactant properties of the soap by forming a solid precipitate (the soap scum). A major component of such
Magnesium silicide in the interior of the unit cell. The coordination numbers of Si and Mg are eight and four, respectively. Magnesium silicide Magnesium silicide, MgSi, is an inorganic compound consisting of magnesium and silicon. It can be produced by heating silicon dioxide, SiO, found in sand, with excess magnesium. The process first forms silicon metal and magnesium oxide, and, if an excess of magnesium is used, the silicide is formed: If an excess of Mg is present, MgSi is formed from the reaction of the remaining magnesium with the silicon: These reactions proceed exothermically. Magnesium silicide is used to create aluminium