Stannic chloride titration

Recently, Mazzocchin et al. have studied several titration methods for determining relatively large amounts of technetium. The most precise results have been obtained by coulometric titration of TcO ions With electrogenerated tin (II) according to the procedure suggested by Bard and Lingaiie . The supporting electrolyte consists of 2.5 M sodium bromide, 0.15 M stannic chloride and 0.2 M hydrochloric acid. The titration reaction is very fast and currents up to 40 mA can readily be employed in the detection of the equivalence point. 

In the preceding chapters it has been shown that the behavior of substances like sulfur trioxide, boron trifluoride, aluminum chloride, stannic chloride, and silver perchlorate is analogous to the beha,vior of H-acids in neutralization, in displacement, and in titrations with indicators. Many acid-catalyzed reactions will be discussed here in order to emphasize the fact that acidity depends on the electrophilic nature of the reagent and not on the presence of any particular element. 

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