A Student-Designed Potentiometric Titration: Quantitative Determination of Iron(II) by Caro's Acid Titration

Abstract

A laboratory experiment involving the feasibility of using Caro's acid, H2SO5, as a titrant in the potentiometric determination of iron (II) is presented. Specific items considered in the experiment include (i) method of endpoint detection; (ii) shelf-life stability of titrant; (iii) accuracy, relative precision and experimental uncertainty; and (iv) which common cations and/or anions (if any) interfere with the titration. Typical student results gave iron (II) concentrations within 1-2 % of the "true" values. Of the 14 cation/anion pairs suggested in the paper, only time(II) was found to interfere with the quantitative determination of iron (II) using Caro's acid titrant.

Conductimetric Titrations: A Predict−Observe−Explain Activity for General Chemistry

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Using Student-Developed, Inquiry-Based Experiments To Investigate the Contributions of Ca and Mg to Water Hardness

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Complexation Effect on Redox Potential of Iron(III)−Iron(II) Couple: A Simple Potentiometric Experiment

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