Soft water 407302 221755328 2008-06-25T23:16:02Z 212.159.23.71 Added link to cation (Ion) wiki {{otheruses4|naturally occurring soft water|man-made soft water|Water softening}} '''Soft water''' the term used to describe types of [[water]] that contain few or no [[calcium]] or [[magnesium]] metal [[Ion#Ions|cations]]. The term is usually related to ''[[hard water]]'', which does contain significant amounts of these ions. Soft Water usually comes from [[peat]] or [[igneous rock]] sources, such as [[granite]] but may also derive from [[sandstone]] sources, since such [[sedimentary rock]]s are usually low in calcium and magnesium. There are water-softening devices used in households and by industry to remove the hardness causing minerals from Hard Water to create artificially Soft Water. Typically such devices exchange the calcium and magnesium ions in the hard water for [[sodium]] ions (ion exchange), or remove most of the soluble species in the water to produce water with little or no mineral content, (de-ionisation). The main benefit of this artificially softened water is that the build-up of solid minerals,( eg [[calcium carbonate]]), in pipe work and on heated surfaces such as in boilers, immersion heaters or hot water cylinders, is controlled or even eliminated. However, softened water tends to be more corrosive to metals such as steel and zinc because these mineral deposits do not form and protect the corroding metal surfaces. Water softened by sodium ion exchange will have a higher sodium ion content than the natural water it was derived from. [[Category:Water]] [[Category:Forms of water]] {{watersupply-stub}} [[ca:Aigua tova]] [[et:Pehme vesi]] [[es:Agua blanda]] [[eo:Malsaturita akvo]] [[ja:軟水]] [[pt:Água macia]] [[simple:Soft water]] [[zh:软水]]