Question

If we want to neutralize the acid rain which is present in rivers than what will u use because calcium and magnesium cannot be used for whole river

Answer 1

The problem with acid lakes is that acid lakes consume water hardness as the acid lakes are neutralized by liming. If the water in the acid lakes were not acidic, the water hardness would most likely be good, as it probably was centuries ago. Calcium and magnesium present in most rock and mineral deposits are dissolved into the water by acidic rain and groundwater. In this case, acid rain performs a useful function of increasing water hardness. Water hardness is nature’s way of removing excess phosphorus from lakes. A common solution to increase water hardness in acid lakes is to add lime, a high-alkalinity calcium compound to the acid lakes. This method is only temporary and very expensive, as it often needs to be applied every year