Water Hardness Quiz

The two types of hardness of water are temporary hardness and permanent hardness. Temporary hardness is due to bicarbonates of calcium and magnesium, which can be removed by boiling the water. On boiling, the bicarbonates are converted into insoluble carbonates of calcium and magnesium. Permanent hardness is due to the presence of other soluble salts of calcium, magnesium, and other metals, which can be removed only by chemical treatments.

Temporary hardness is due to bicarbonates of calcium and magnesium, which can be removed by boiling the water. On boiling, the bicarbonates are converted into insoluble carbonates of calcium and magnesium. Permanent hardness is due to the presence of other soluble salts of calcium, magnesium, and other metals, which can be removed only by chemical treatments.

The hardness of water is determined by titrating a known volume of water sample with EDTA, using Eriochrome Black T (EBT) as an indicator, in the presence of ammonium hydroxide ammonium chloride buffer (pH 10).

<p>The sum of temporary hardness and permanent hardness is known as total hardness. The hardness is expressed in ppm or mg/L of calcium carbonate equivalent.</p> Signup and view all the answers

<p>Hard water does not give lather easily with soap because the hardness causing ions react with soap to form insoluble soap, precipitating in the form of a scum.</p> Signup and view all the answers