Merck, 1.11174, Chlorine and pH Test

General description
(free chlorine, total chlorine, and pH) Method: colorimetric with color-matching vessel 0.1 - 0.3 - 0.6 - 1.0 - 1.5 mg/l Cl₂ pH: 6.8 - 7.1 - 7.4 - 7.6 - 7.8 MQuant®
Chlorine containing disinfectants are most widely used. They are applied particularly to disinfect drinking water and swimming pool water. This MQuant® Chlorine and pH test (formally MColortest®) measures chlorine and pH and evaluates the color reactions based on the transmitted light method. So even turbid and colored water samples can be analyzed without further preparation. The color matching vessel is made of very durable, lightfast plastic, thus suitable for industrial areas and wet environments.
Using the refill packs 1.11143 and 1.11157, the original test kit can be used for a very long time, making it a particularly economical and ecological system.

Method
In weakly acidic solution free chlorine reacts with diethyl-p-phenylenediamine (DPD) to form a red-violet dye. Combined chlorine reacts only after the addition of iodide ions. This permits free chlorine to be distinguished from combined chlorine.
The pH determination takes place by means of chlorine-resistant phenol red indicator solution, which changes color from yellow to red-violet in the pH range of 6.5 8.2.

This test is not suited for seawater.
Water in public and private swimming pools must be disinfecting to kill bacteria and viruses. Chlorine-containing preparations or even chlorine gas itself are usually used for this purpose. To check the content of chlorine and the pH value is essential.
Legal Information
MCOLORTEST is a registered trademark of Merck KGaA, Darmstadt, Germany
MQUANT is a registered trademark of Merck KGaA, Darmstadt, Germany