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TITRATIONS BASED ON REDOX REACTIONS [311]
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15
TITRATIONS BASED ON REDOX REACTIONS [311] I N most instances, the field of redox reactions is excluded from conductometric measurements, because either the change in the number of ions in solution is minimal, or else a type of medium must be used in which the changes in conductivity caused by the titration reaction are relatively very small (con centrated acids or bases). Redox reactions have recently been extensively studied by Ceausescu [53-56]. Jander and Pfundt [166] proposed only the titration of iron (Π) with dichromate and of arsenite with iodine. Ceausescu systematized the reactions and prepared a table of those where an acid is formed or where an acid or base is decomposed; these are the reactions t h a t are suitable for con ductometric (oscillometric) purposes. The oxidation reactions of iodine are the simplest to be applied to conductometry and oscillometry [13, 294]. In these experi ments iodine dissolved in methanol is used as a titrant. Sulphite is titrated in its approximately 0*3 per cent acetic acid solution, while arsenite and antimonite are titrated in a 0*2 N aqueous ammonia solution.
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15
TITRATIONS BASED ON REDOX REACTIONS [311] I N most instances, the field of redox reactions is excluded from conductometric measurements, because either the change in the number of ions in solution is minimal, or else a type of medium must be used in which the changes in conductivity caused by the titration reaction are relatively very small (con centrated acids or bases). Redox reactions have recently been extensively studied by Ceausescu [53-56]. Jander and Pfundt [166] proposed only the titration of iron (Π) with dichromate and of arsenite with iodine. Ceausescu systematized the reactions and prepared a table of those where an acid is formed or where an acid or base is decomposed; these are the reactions t h a t are suitable for con ductometric (oscillometric) purposes. The oxidation reactions of iodine are the simplest to be applied to conductometry and oscillometry [13, 294]. In these experi ments iodine dissolved in methanol is used as a titrant. Sulphite is titrated in its approximately 0*3 per cent acetic acid solution, while arsenite and antimonite are titrated in a 0*2 N aqueous ammonia solution.
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