Merck, 1.10046.0001, Total Hardness Test

Method: Colorimetric, with test strips, >5 - >10 - >15 - >20 - >25°d, >6 - >13 - >19 - >25 - >31°e, >9 - >18 - >27 - >36 - >45°f, MQuant® The MQuant® total hardness test strips can be used to measure water hardness. The hardness (total hardness) of a given water is due to its content of salts of the alkaline earth metals calcium, magnesium, strontium, and barium (“hardening constituents”, later compounds only in traces). In the presence of a green indicator the hardness ions Ca²⁺ und Mg²⁺ react with Titriplex® III to form a colorless, stable complex. The hardness ions that are present in excess relative to Titriplex® III react with the indicator to form a red complex. The reaction zones of the test strip, which are impregnated with differing amounts of Titriplex® III, thus assume a green to red color, depending on the hardness of the water sample. The hardness is measured semi-quantitatively by visual comparison of the reaction zones with the color rows of a color scale. For other sensitivities and graduations please consider the other MQuant® tests as well as our Reflectoquant® and Spectroquant® portfolio.