ISO 5790:1979

Covers a method enabling quantities of chloride eceeding 1 mg in the test portion to be determined with an absolute error of 0,2 to 0,5 mg, according to the concentration of the standard volumetric solution used. The principle of determination is based on the conversion of chloride ions into weakly ionized mercury(II) chloride, using highly ionized standard volumetric mercury(II) nitrate solution, and detection of the end-point by reaction of the excess of mercury(II) nitrate with 1,5-diphenyl-carbazone used as an indicator, by the apparance of a violet colour.