ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Use of carbon indicator electrodes in potentiometric neutralization titrations. III. Carbon electrodes in the anhydrous pyridine medium

J. Berčík and Z. Hladký

Department of Analytical Chemistry, Slovak Technical University, Bratislava

Abstract: The use of chem. activated C electrodes (carbon black impregnated with Teflon, electrographic EK37 impregnated with Teflex, and glassy carbon) for indication in potentiometric neutralization titrns. of acidic compds. in anhyd. pyridine was described. Before every titrn., the bottom active surface of the electrode was roughened by a fine-grain abrasive paper and activated chem. by immersing into aq. 0.2M KMnO₄ in 0.5M H₂SO₄. The compds. titrated were: phenylcinchoninic, benzoic, stearic, phenylacetic, and p-hydroxybenzoic acids, p-nitrophenol, 2,4,6-trinitrophenol, 3,5-dichlorophenol, thymol, and atropinium sulfate. Glassy C electrodes show the greatest change in potential, compared with both glass and Au electrodes. The chem. activated graphite electrode was better suited for titrns. with NaOMe than glass electrodes. The results of the titrns. with Bu₃MeNOH are equally good with graphite electrodes as those with glass electrodes.

Full paper in Portable Document Format: 2210a768.pdf (in Slovak)

Chemical Papers 22 (10) 768–775 (1968)