Water Hardness and Treatment

The different types of hardness in water are temporary hardness, caused by Ca and Mg bicarbonate, and permanent hardness, caused by other salts like carbonate, sulphate, and chloride of Ca and Mg. Temporary hardness can be removed by boiling or adding hydrated lime, while permanent hardness requires other methods like ion exchange for softening.

Hard water is formed due to the presence of minerals like Ca and Mg, which are not removed by sedimentation or filtration. When hard water reacts with soap (sodium salt of stearic acid or palmitic acid), it gives a curdy precipitate as insoluble calcium stearate or magnesium stearate, which does not produce lather.

Temporary hardness of water is caused by Ca and Mg bicarbonate. It can be removed by simply boiling water, as the bicarbonate is converted into insoluble carbonate precipitates. It can also be removed by adding hydrated lime to precipitate insoluble carbonate.

<p>The Langlier Index is a measure of the saturation of water with calcium carbonate. It is used to determine the tendency of water to form scale or dissolve existing scale in water pipes and equipment. It helps in maintaining the water's balance and preventing corrosion or scale formation in water systems.</p> Signup and view all the answers

<p>Softening of water using the ion exchange method involves replacing the calcium and magnesium ions in the water with sodium ions. This is achieved by passing water through a resin bed containing sodium ions, which attract and exchange with the calcium and magnesium ions, resulting in softened water.</p> Signup and view all the answers