Determination of analytical parameters in drinking water by flow injection analysis. Part 2. Simultaneous determination of calcium and magnesium

Abstract
A method for the simultaneous determination of calcium and magnesium (hardness) in water by flow injection analysis (FIA) is suggested. The method is applied to the determination of these parameters in natural, drinking, urban and bottled waters. The determinations are performed by an FIA titration with spectrophotometric detection. The chemical systems used are conventional, i.e., murexide-EDTA for calcium and eriochrome black T-EDTA for the sum of calcium and magnesium, the concentration of the latter being obtained by difference.