The representational levels: Influences and contributions to research in chemical education

Chemistry is considered a difficult subject to study since it comprises microscopic,macroscopic,and symbolic components. this paper provides a comprehensive review of the literature on the representational levels (macroscopic,microscopic,and symbolic) that involve models of thinking in chemistry,and it summarizes what is currently known and provides guidance for further research. this work reports the outcomes of theoretical and empirical studies about the representative levels in chemistry,science,and teacher education. the outcomes present a major concern around the difficulties and abilities of high school and undergraduate students in understanding chemistry in all the representational levels. nevertheless,few studies were found about the teaching of educational programs,which shows that scientific studies on this topic are still lacking.