Inability to link the acid-base concepts with daily life phenomena (as contexts) highlights the need for further research on the context-based acid-base chemistry. In this vein, the aim of this study is to investigate the effects of different teaching designs (REACT strategy, 5Es learning model and traditional (existing) instruction) relevant with "acids and bases" subject on pre-service science teachers' conceptions and attitudes towards chemistry and to compare them with each other. Within quasi-experimental research design, the sample comprised of 95 pre-service science teachers from Faculty of Education in Giresun University, Turkey. Three intact groups were randomly assigned as either experimental and control groups. To gather data, Acid-Base Chemistry Concept Test (ABCCT), Chemistry Attitudes and Experiences Questionnaire (CAEQ) and semistructured interviews were used. The results denote that REACT strategy is effective in helping the pre-service science teachers retain their gained conceptions in long-term memory whilst 5Es learning model is efficient in achieving conceptual learning. Finally, future studies should test the effects of REACT strategy and 5Es learning model on different variables (i.e. sample, subject, scientific process skills, scientific inquiry) over a longer period of time (i.e. one semester or one-year).