English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

Results obtained in potentiometric titrations of Fe(II), Mn(II), Fe(CN)64-, C2O42- and As(III) with standard potassium permanganate solution, are presented. The titration end point (TEP) was detected with a universal electrode whose sensor is natural crystalline pyrite. The titrations of As(III) were carried out in HCl (1.2 M) and H2SO4 solutions (0.1- 4.5 M), whereas oxalate was determined in H2SO4 (0.1-4.5 M). Iron(II) and hexacyanoferrate(II) were titrated in H2SO4 and also in H3PO4 solutions (0.1-4.5 M). The titrations of Mn(II) were performed in H2P2O72- media at pH 4.0, 5.0, 6.0 and 7.0. The results obtained by using the pyrite electrode were compared with those obtained by the application of a Pt-electrode, and good agreement, reproducibility and accuracy were obtained. The potentials in the course of the titration and at the end-point (TEP) are rapidly established. The potential changes at the TEP ranged from 90 to 330 mV/0.1 mL, depending on the titrated system. The highest changes were observed in titrations of Fe(II) in H3PO4 (240-330 mV/0.1 mL). Reversed titrations were also performed and accurate and reproducible results were obtained

Natural Monocrystalline Pyrite as Sensor for Potentiometric Redox Titrations. Part I. Titrations with Permanganate