R P Singh
Articles written in Proceedings – Section A
Volume 55 Issue 4 April 1962 pp 195-199
Alloxantin gives a deep yellowish-red colour with molybdates in aqueous solution. This colour reaction has been investigated and utilised for spectrophotometric determination of molybdenum. The colour has maximum intensity between pH range 3·3–3·9. It obeys Beer’s law at 400 m
Volume 56 Issue 3 September 1962 pp 125-129
Chrysin forms a yellow coloured complex with thorium. This colour reaction has been investigated and utilised for spectrophotometric determination of thorium. The colour has maximum intensity at pH 2·8. It obeys Beer-Lambert’s law at 380 m
Volume 57 Issue 2 February 1963 pp 79-87
Estimations of lead, barium, thallium and silver have been carried out in aqueous or ethanol-water media using a 30 Mc. unit. It has been found that lead and barium can be estimated by both direct and reverse titrations in aqueous medium. In case of silver and thallium (I), the addition of an equal volume of ethanol or methanol to the solution to be titrated was found essential for accuracy and reproducibility. Limits of tolerance for some ionic constituents which are frequently associated with these cations have also been determined. Thallium has been estimated by both direct as well as reverse titrations, but in case of silver, reverse titrations gave low results. The method requires much less time for the estimations as compared to other methods and the results fall within the ordinary limits of accuracy required.
Volume 57 Issue 4 April 1963 pp 259-265
The spectrophotometric determination of zirconium is described, based on the formation of a yellow coloured complex between zirconium and galangin. Maximum absorption by the reaction product only at one specific wavelength (410 mµ) in the acidity range of 0·5 N-HCl to pH 4·5, suggests the formation of only one complex. The complex, not extractable by usual organic solvents, has been studied in 40% alcoholic medium. It obeys Beer’s law from 1 to 6 p.p.m. of metal ion concentration and contains the two components in the molar ratio of 1:1. The effect of the reagent on other ions has been qualitatively studied. Also, the effect of foreign ions on the complex has been investigated.
Volume 68 Issue 2 August 1968 pp 82-87