What type of hardness can be reduced by boiling water?

Boiling water primarily reduces temporary hardness, which is commonly caused by the presence of dissolved bicarbonate minerals in the water, such as calcium bicarbonate and magnesium bicarbonate. When water containing these compounds is boiled, the heat causes the bicarbonates to decompose, resulting in the formation of carbonates that precipitate out as solid compounds. This process effectively reduces the amount of hardness in the water because the solid carbonates can then be removed from the water.

On the other hand, permanent hardness arises from the presence of calcium and magnesium sulfates or chlorides, which do not precipitate upon boiling. Therefore, boiling is not an effective method for reducing permanent hardness. Understanding the distinction between temporary and permanent hardness is crucial for effective water treatment practices.