Drinking water containing magnesium

Drinking waters containing calcium and magnesium salts at a few hundred ppm... 

Soft drinks will contain sodium (from water and added sodium salts, e.g. benzoate, saccharin, citrate, CMC), calcium and magnesium (from water and fruit materials) and potassium and phosphate (from fruit materials). 

Many areas have household water containing calcium, magnesium, and iron ions. Although these mineral-rich waters can be healthful for drinking, the ions react with soaps to form insoluble salts called hard-water scum. The following equation shows the reaction of a soap with calcium, common in areas where water comes in contact with limestone rocks. 

Sodium ions may naturally be present in drinking water if the supply is brackish, like many water sources in Central Asia and the Middle East. Above about 300-400 ppm of sodium chloride, the water is unpalatable on account of its chloride content, and special purification measures, such as reverse osmosis (see below Section 6) are required. Naturally soft water frequently contains sodium rather than the hardness cations calcium and magnesium, while water softening artificially in domestic water softeners has the hardness cations replaced by sodium (see below Section 5). Even though... 

First, we must understand that virtually no water is pure. Like most liquids we encounter, water is a solution containing a number of different elements and compounds. Pure water can be made only in the chemist s laboratory. Consequently, we will focus on what substances lurk in drinking water some of these, such as calcium or magnesium ions, have positive health benefits, while others, such as bacteria or lead, are harmful. 

Figure 13.25 Magnesium anodes being prepared for use in soii (a) eiectricai connection being soidered (b) insuiating tar added to protect the eiectricai connection (c) suifate rich powder added to the porous container to provide good anode current efficiency. (Courtesy of Drinking Water Services, City of Ottawa)...

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