Removal of Sodium Diclofenac from Aqueous Medium Using Layered Double Hydroxide: a Thermodynamic and Theoretical Approach

The proposal presents the discussion and application of an investigative experiment for the construction of acid-base titration curves from the variation of the visual appearance of the colors when using red cabbage extract as an indicator. The research was carried out with undergraduate students, involving the problematization of the steps, raising hypotheses and, at the end, a dialogued conversation between students and professors, stimulating thinking in a scientific way, developing observation and reflection skills. Based on observations of the titrator’s color variations at each titrant increment and by comparison with a standard color scale, that the effects of the dilutions of both can be evaluated in the different profiles of the titration curves. In this investigation, we understand that the color variations established by the different anthocyanin structures are crucial for a better understanding of the observed profiles of the titration curves, correlating the limiting and excess reagents with each point of the analyzed curve. This methodological proposal of investigative experimentation, with active student participation, contributed to improve the learning of undergraduate students, regarding the construction of titration curves involving acids and bases of different concentrations from the visualization of the colors of the red cabbage extract.

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F. A. do Amaral

Papers

Removal of Sodium Diclofenac from Aqueous Medium Using Layered Double Hydroxide: a Thermodynamic and Theoretical Approach

Proposal and Application for an Investigative Experiment for Construction of Titration Curves with Purple Cabbage Extract