Sequential titration of iron(II) and vanadium(IV) mixtures with cerium(IV) sulphate, with ferroins as indicators.

The titration of vanadium(IV) with cerium(IV) sulphate, with nitroferroin as indicator, is proposed. Unlike ferroin, the indicator does not need a catalyst in this system. By suitable choice of experimental conditions iron(II) can be titrated first to a ferroin end-point and then vanadium(IV) to a nitroferroin end-point.

Sequential titration of iron(II), antimony(III) and arsenic(III) in binary or ternary mixture.

A simple titrimetric procedure for the determination of iron(II), antimony(III) and arsenic-(III) in a mixture, with cerium(IV) sulphate as titrant, is proposed. The end-points can all be detected with ferroin or potentiometrically. Phosphoric acid medium is used for titration of the iron(II), then acetic acid medium for the titration of antimony(III), and finally the arsenic(III) is titrated in presence of iodine as catalyst. The procedure utilizes a single portion of test solution; it can be adopted for the analysis of binary mixtures.

Titration of vanadium(IV) with cerium(IV) sulphate, with ferroin as indicator, in aqueous acetone as facile reaction medium An analytical and mechanistic study.

A new procedure for the titration of vanadium(IV) with cerium(IV) sulphate, with ferroin as indicator, in aqueous acetone medium is reported. A differential determination of iron(II) and vanadium(IV) is also possible. A probable mechanism for the fast ferriin-vanadium(IV) reaction in acetone medium is given.

A new and rapid titration of antimony(III) with potassium dichromate, with iron(II) as inductor.

The optimum conditions for the titration of antimony(III) with dichromate, and diphenyl-aminesulphonic acid as indicator, have been established. No iodine catalyst is used; the analytical reaction is based on an induced reaction with iron(II) as inductor. The titration can be done as easily as an iron(II) titration and the end-point is equally sharp. Titrations are possible with 0.01N solutions.