Bharat R. Sant

Oxidation of hydroxylamine by ferricyanide in presence of zinc sulfate: A rapid method for estimating hydroxylamine and hydrazine in a mixture

Abstract The direct titration of alkaline ferricyanide in presence of zinc sulfate with hydroxylamine sulfate has been studied. A clear white precipitate of zinc potassium ferrocyanide indicates the end-point. Hydroxylamine is oxidized to nitric acid and water, and millingram-quaantities of hydroxylamine; can be determinred. In the absence of zinc sulfate and in weakly alkaline medium, hydrazine and hydroxylamine are converted to nitrogen, while in presence of zine sulfate hydrazine is oxidized to nitrogen By ferricyanide oxidation of a mixed sample uinler different conditions, hydrarine and hydroxylamine when present together can be determined rapidly.

A catalog of retention times of a number of organic compounds

Summary The relative retention times of organic compounds on tri- m -tolyl phosphate and β,β′-oxydipropionitrile columns have been determined and tabulated. The method for the use of these tables has been suggested. Through the use of the two columns with subsequent reference to the data on the respective retention times, a wide variety of compounds can be tentatively identified.

Quantitative oxidations by potassium ferricyanide

Abstract Titrimetric methods using potassium ferricyanide as an oxidant for the estimation of various inorganic and organic substances are reviewed. An attempt has been made to evaluate the importance of these methods. Although the emphasis is on the literature that appeared in the past five years, some older procedures are included because of their significance.

Direct titration of potassium ferricyanide with hydrazine sulphate in presence of zinc sulphate determination of hydrazine

Abstract Operative conditions for direct titration of potassium ferricyanide solution with a solution of hydrazine sulphate which contains zinc sulphate are described. The results are comparable with those obtained by the standard iodate procedure. The chief advantages of the present method of estimating hydrazine are (1) titration in slightly acidic medium and (2) no indicator is required. Determination of substituted hydrazines, hydroxylamine and other reducing substances on similar lines is suggested.

Direct titration of ferricyanide in presence of zinc sulfate : Determination of nitrite

Abstract A rapid oxidimetric method for nitrite estimation, based upon the titration of ferricyanide in presence of zinc sulfate in aqueous or very slightly alkaline medium with a solution of sodium or potassium nitrite is described. Complete decolorization of the solution marks the end-point. The presence of large quantities of nitrate causes no interference

High frequency titrations: The silver-thiocyanate reaction

A high frequency (oscillometric) method for the titrimetric determination of small amounts of silver at dilutions down to 14000M with ammonium or potassium thiocyanate is described. Reverse titrations in the same order of dilution are also feasible. Oscillometric studies on the formation of soluble mercuric thiocyanate and of the sparingly soluble zinc tetracyanatomercuriate(l1) are in progress.

2-Mercaptoacetic (thioglycollic) acid as a reagent for zirconium

Abstract Thioglycollic acid has been shown to be a suitable reagent for the quantitative precipitation of zirconium at a pH of about 4.5. A basic zirconyl thioglycollate is formed and therefore the analysis is completed by weighing the zirconium oxide. Interference due to several metal ions is discussed.

Thiodiglycolic acid as a reagent for zirconium

Thiodiglycolic acid is shown to be a suitable precipitating reagent for zirconium. The analysis is completed by igniting the precipitate and weighing the ZrO2. Several metal ions do not interfere. Interference due to cerium(IV) is avoided by reducing it initially to cerium(III). Estimation of zirconium can be carried out in presence of thorium. The composition of the Complex is slightly variable but corresponds to zirconyl thiodiglycolate: O =

Amperometric titrations with rotated platinum electrode: Determination of hydrazine by potassium bromate

The reaction between hydrazine and potassium bromate is studied amperometrically at rotating platinum electrode. The bromate titration is performed at an applied e.m.f. of zero (versus S.C.E.) and in the presence of bromide and 1–5N sulfuric acid or 0.5–4N hydrochloric acid. Quantities ranging from 30 μg to 3 mg of hydrazine can be estimated accurately by this method. Determination of phenylhydrazine, Semicarbazide and other oxidizable materials on similar lines is suggested.

High frequency titrations: The mercury(ii)-thiocyanate reaction

Abstract Soluble complex-formation of mercury(II) thiocyanate has been studied oscillometrically. The titration of mercury(II) nitrate with thiocyanate gives one inflection corresponding to the formation of Hg(SCN)2, while in the reverse titration the formation of Hg(SCN)+ is also indecated. The method is useful for a rapid determination of very small quantities of mercury or thiocyanate in highly dilute solutions. The titrations can be effected in presence of nitric acid provided its total acidity in the system does not exceed about 1 300 N. Further Work on the mercury(II) -halide and mercury(II)-cyanide reactions is in progress.