Several research studies revealed that students had misconceptions about different scientific concepts. To eliminate these misconceptions, conceptual change model was proposed by Posner (1982). It involves four steps as dissatisfaction, intelligibility, plausibility and fruitfulness in order to have conceptual change in students’ minds. Different teaching strategies, based on conceptual change model, were developed. One of the them is the conceptual change text. In the conceptual change texts, firstly, students are expected to make a prediction about the given situation, which is designed to activate students’ misconceptions if they exist. This step provides dissatisfaction. Afterwards, scientific explanations with persuasive examples are presented to provide intelligibility and plausibility. Conceptual change texts also involve application of new concepts to other areas, which promotes fruitfulness (Roth, 1985). Like other scientific concepts, research studies indicated common misconceptions of students about energy in chemical reactions (Johnstone, MacDonald & Webb, 1977; BouJaoude, 1991; Boo, 1998; Greenbowe & Meltzer, 2003; Paik, Cho & Go, 2007). In this study, conceptual change text instruction considering conceptual change model was used to eliminate students’ misconceptions in the context of energy in chemical reactions concepts. Research question of this study is: What is the effectiveness of conceptual change text-oriented instruction on students’ understanding of energy in chemical reactions concepts?

Sample Convenience sampling technique was used in this study. Two classes, including 30 10th grade students each, were the participants Classes were randomly assigned as experimental group and control groups. These classes were instructed by the same teacher. Control group students were instructed traditionally whereas experimental group students were taught via conceptual change text. Conceptual change texts were deveoped by the researchers. During the treatment, firstly, the situations were given to let students think individually and then class discussion took place in order to provide dissatisfaction. Then, a text including scientific explanations with persuasive examples were given and students read the text and discussed discrepancies between their previous ideas and scientific explanations to promote intelligibility and plausibility of the new concept. Since examples used in the texts were mostly related to daily life, this helped students apply the related knowledge into other contexts, which provided fruitfulness. Instruments Energy in Chemical Reactions Concept Test (ECT) and Science Process Skill Test (SPST) were used in this study. ECT, developed by researchers, included 20 multiple-choice items. The test items were constructed based on students’ misconceptions related to Energy in Chemical Reactions in the context of heat and temperature, exothermic and endothermic reactions, bond energy, burning reactions, enthalpy and calorimeter. Reliability of the ECT was found as 0.70. This test was given to the participants before and after treatments. Another instrument used in this study was Science Process Skill Test (SPST). It was developed by Okey, Wise and Burns (1982) and adapted into Turkish by Geban, Aşkar and Özkan (1992). It was used to control the effect of science process skills on achievement. Analysis One-way Analysis of Covariance (ANCOVA) was conducted to understand the effectiveness of conceptual change text-oriented instruction on students’ understanding of energy in chemical reactions when science process skills were controlled.

Results and Implications Analysis of data indicated that there was a significant mean difference between students taught traditionally and those instructed by conceptual change text oriented instruction with respect to students’ understanding of energy in chemical reactions when science process skills were assigned as covariate (F (1,57) = 16,91, p<.05, 2= 0.23). Mean score of post-ECT for the control group was 7.86, and for the experimental group, it was 11.70. This study revealed that conceptual change texts can be used in chemistry classes to remedy students’ misconceptions. Therefore, chemistry teachers should be informed how to prepare and use conceptual change texts efficiently in their classes. Further studies can be carried out including conceptual change texts accompanied by other methods based on conceptual change model such as demonstration, analogies.