不适用于分析农用混合物，如除草剂或杀虫剂。指示处理clorates时的风险。试样在水中溶解，并在硫酸和正磷酸介质中以已知量还原铁盐（II）。以二苯胺-4-磺酸钡溶液为指示剂，用重铬酸钾标准体积溶液滴定过量的铁（II）盐。

Not applicable to the analysis of mixtures for agricultural use such as herbicides or pesticides. Indicates the risk in handling with clorates. Dissolution of the test portion in water and reduction by a known quantity, in access, of an iron(II) salt in a sulphuric acid and orthophosphoric acid medium. Titration of the excess iron(II) salt with a standard volumetric solution of potassium dichromate in the presence of barium diphenylamine-4-sulphonate solution as indicator.