Measurement of Acidity in Commercial Vinegar as a Didactic Strategy for Teaching the Acid–Base Titration Process

Abstract

Vinegar is a product of daily consumption whose quality depends on its degree of acidity, determined by the concentration of acetic acid. This study addressed the need to apply didactic strategies that enable chemistry students to link acid–base theory with real-life contexts. The objective was to evaluate the acidity of commercial vinegars through titration, integrating this procedure as a pedagogical resource to develop analytical and experimental skills. Twelve brands of white vinegar available in Guayaquil, Ecuador, were analyzed, measuring physicochemical parameters as pH, density, and total acidity. The results were subjected to descriptive statistics, normality tests, analysis of variance, and mean comparison tests. The findings showed significant differences in acidity, with values ranging from 2.94% to 4.98% m/m, identifying two brands outside the recommended range (4–6%). The pH ranged from 2.14 to 2.98 units, while density showed low variability (1.0036–1.0049 g/mL). More than 80% of the students evaluated the practice positively. In conclusion, the titration of commercial vinegars is confirmed as an effective strategy for teaching chemistry, as it integrates theory and practice with real applications