Which of the following ions is a pollutant in drinking water even in trace amounts?
Answer Details
The pollutant in drinking water, even in trace amounts, among the given ions is Hg2+. Mercury (Hg) and its compounds are highly toxic and can cause serious health problems, including neurological and developmental damage, even at low concentrations. Therefore, the presence of mercury in drinking water can be harmful to human health. The other ions listed, Ca2+, Mg2+, and Fe2+, are essential minerals that are generally safe to consume in drinking water, and they do not pose a significant health risk in trace amounts.