Test strip for determining the concentration of complexants in fluids

摘要

A test strip (1) determines the presence of chemical complexing agents in liquids. The test strip bears an indicator paper (3) impregnated with distilled water. The distilled water contains bismuth nitrate and Xylenol orange in quantities which, after insertion of the test strip into the sample liquid, change color in the presence of complexing agents. - The test strip does not change color when inserted into a liquid not containing complexing agents. The pH of the impregnation solution is set at s 2. The impregnation solution contains 0.1-2 wt.% Xylenol orange with reference to distilled water. The impregnation solution contains at least 0.02 wt.% bismuth nitrate w.r.t distilled water. The pH value is set by the admixture of 40-60 wt.% citric acid w.r.t distilled water.