Which substance may be used for the removal of Iron and Manganese in water?

Chlorine is commonly used for the removal of iron and manganese in water due to its strong oxidizing properties. When chlorine is added to water containing these metals, it oxidizes soluble iron and manganese to their insoluble forms, which can then be effectively removed through filtration. This oxidation process converts ferrous iron (Fe²⁺) and manganese (Mn²⁺) into ferric iron (Fe³⁺) and manganese dioxide (MnO₂), respectively. Both of these oxidized forms precipitate out of the solution, making it easier to separate them from the water.

The other substances listed do not serve this purpose effectively. Ozone, while also a strong oxidizer, is typically used in more specialized applications and may not be the first choice for iron and manganese removal in standard water treatment processes. Calcium is primarily used to soften water and is not effective for the specific removal of iron and manganese. Sodium does not play a direct role in the oxidation or removal of these metals and is more often associated with water softening processes.