can we express water hardness in any other term like MgCO3 etc
2007-07-20 00:12:46 · 2 answers · asked by saeed 1 in Science & Mathematics ➔ Chemistry
Hard water is water that has a high mineral content (water with a low mineral content is known as soft water). This content usually consists of high levels of metal ions, mainly calcium (Ca) and magnesium (Mg) in the form of carbonates, but may include several other metals as well as bicarbonates and sulfates. It is not generally dangerous. The simplest way to determine if water is hard or soft is the lather/froth test. If the water is very soft, soap will tend to lather up easily when agitated, whereas with hard water it will not. Toothpaste will also not froth well in hard water. More exact methods of 'hardness' detection use a wet titration method to determine hardness.
Total water 'hardness' (including both Ca2+ and Mg2+ ions) is reported as ppm w/v (or mg/L) of CaCO3. Water hardness usually measures the total concentration of Ca and Mg, the two most prevalent divalent metal ions, although in some geographical locations iron, aluminium, and manganese may also be present at elevated levels. Calcium usually enters the water from either CaCO3, as limestone or chalk or from mineral deposits of CaSO4. The predominant source of magnesium is dolomite, CaMg(CO3)2.
2007-07-20 02:11:59 · answer #1 · answered by Gr8life 2 · 1⤊ 0⤋
I believe that Ca is the most common divalent cation for that purpose
2007-07-20 00:24:56 · answer #2 · answered by maussy 7 · 0⤊ 0⤋