AMMONIA STANDARD SOLUTION

PURPOSE:To obtain a stable standard solution generating no change of a concn. of an ammonium ion even after long-term preservation by using a standard solution containing a buffer, an ammonium salt of a definite concn. and having a specific pH value as a standard solution for determining the ammonium ion in a liquid. CONSTITUTION:A standard solution is mainly constituted of an ammonium salt, a buffer and a preservative and has pH of 2.8-4.0. As the ammonium salt, chloride, sulfate and nitrate are used and, as the buffer, amino acid glycyl glycine or a derivative thereof is used. As the preservative, a p-chlorophenol derivative or a benzothiazole derivative is pref.