Some observations on an indirect atomic absorption spectrophotometric method for the microdetermination of chlorine or bromine in organic compounds

An atomic absorption spectrophotometric method for the microdetermination of chlorine or bromine in organic compounds is described; it is based on oxygen flask combustion to yield chloride or bromide, which is then reacted with an excess of solid silver chromate, followed by collection of the combined unreacted silver chromate and chloride or bromide preipitate and AAS determination of the free chromate (equivalent of the chloride or bromide originally present) at 358.2 nm. The method was applied satisfactorily to a wide range of chlorine or bromine containing organic compounds with an average absolute error of ± 0.23 and a coefficient of variation (seven determinations) of better than 2%.