Kinetic and Thermodynamic Insights into the Thermal Degradation of Vitamin B6: From Laboratory Experiment to Educational Model

This study provides an informative thermo-kinetic comparison of vitamin B6 (pyridoxine hydrochloride) formulations produced by British and Emirati pharmaceutical companies. The experiment, designed as an instructive model in pharmaceutical chemistry, illustrates the correlation between temperature and the rate of chemical decomposition through UV–Vis spectrophotometric analysis at 290 nm. Using the Arrhenius and Eyring models, we found kinetic and thermodynamic parameters such as activation energy (Ea), enthalpy (ΔH), entropy (ΔS), and Gibbs free energy (ΔG). The Emirati formulation had a melting point of 210 °C and higher ΔH‡ and ΔG‡ values. This means that it was more thermally and molecularly stable, which means that it had stronger internal bonds and was less likely to break down when heated. The British formulation, however, had a lower melting point (184 °C) and broke down more quickly, which suggests that it was less crystalline. This study provides a replicable laboratory framework for imparting pharmaceutical stability and quality assessment from both scientific and pedagogical perspectives, emphasizing the integration of kinetic and thermodynamic analysis into chemistry education.