Exploring physical sciences learners’ graphical interpretation of rate and extent of reaction graphs

Graphs are very important in all areas of science, and they are an essential part of tertiary, high school, and primary school learning, worldwide. A solid understanding of graphical interpretation is essential for understanding today's world and becoming scientifically literate. The aim of this study was to explore grade 12 learners’ graphical interpretation of the rate and extent of reaction topic. A mixed-method methodology was adopted for this study. A purposive sampling technique was used to sample participants from the accessible population in King Cetshwayo District KwaZulu-Natal province in South Africa. One-hundred and forty-six (146) grade 12 Physical Sciences learners formed the sample. A validated two-tier diagnostic questionnaire and semi-structured interviews were used to collect data. Quantitative data were analysed using SPSS version 25 and inductive coding was used to qualitative data. The Johnstone triangle and the Peircean semiotic modes were employed as the theoretical framework. The findings indicated that learners rely on definitions to interpret graphs. Most of the learners failed to interpret the salient features of the graphs. The findings of this study are diagnostic, and they assist module designers and educators in determining challenges learners face when interpreting graphs in chemistry. Implications for instructional approaches particular to the rate of reaction graphs are discussed. Further studies are needed on instructional practices and their effect on students’ ability to interpret rate and extent of reaction graphs. Keywords: Graphical interpretation; rate and extent of reaction; Johnstone triangle