The role of virtual laboratories in advancing student learning on acid–base equilibrium

Abstract This study investigated the effectiveness of integrating virtual laboratories into secondary school chemistry instruction on acid–base equilibrium concepts in Addis Ababa. It examined the impact of simulation-based virtual laboratories on students’ academic achievement, conceptual understanding, engagement, and skill development. PhET Interactive Simulations, a free platform developed by the University of Colorado Boulder, was used for its multilingual support, device compatibility, and suitability for resource-limited schools. A quasi-experimental, mixed-methods design involved 66 Grade 12 students divided into an intervention group and a comparison group. The comparison group completed traditional curriculum-guided laboratory activities, while the intervention group supplemented these experiments with virtual pre-lab simulations. For instance, in an acid–base titration exercise, intervention students used simulations to predict pH changes before performing the experiment, whereas the comparison group proceeded directly to hands-on work. Quantitative analysis using pre- and post-tests revealed statistically significant improvements in the intervention group, although the effect size was small (Cohen’s d = 0.16), likely due to the short intervention and modest sample size. Qualitative interviews indicated that virtual laboratories enhanced engagement, understanding, and collaboration despite occasional access challenges. Overall, virtual laboratories can effectively complement traditional instruction when software accessibility and equitable technology use are ensured.