Comparison of the sub- and super-equivalence and substoichiometric methods of isotope dilution analysis for the determination of a trace amount of antimony

The sub- and super-equivalence methods of isotope dilution analysis (SSE-IDA) have been compared with substoichiometric isotope dilution analysis (Subst-IDA) for the determination of a trace amount of antimony by means of a redox reaction. For this comparison, the difference between the amount separated and the theoretical value was determined under various conditions. Under conditions in which the substoichiometric reaction and separation gave unsatisfactory results, accurate determination could still be performed by SSE-IDA. The reason for this is discussed.