An analysis of prospective chemistry teachers’ cognitive structures through flow map method: The subject of oxidation and reduction

Case study—one of the qualitative research methods—was used in this study. Case study is an approach used in searching for answers to scientific questions (Büyüköztürk, Kılıç Çakmak, Akgün, Karadeniz, & Demirel, 2013).

Study Group
Purposeful sampling method was employed in this study, and 8 prospective chemistry teachers from a group of students who had taken general chemistry and analytical chemistry courses were included in the study. Through purposeful sampling method, key people can be chosen to collect more extensive and in-depth data in a group instead of focusing on all participants in the group (Büyüköztürk et al., 2013).

Data Collection Tool
Flow map method
The subject of oxidation and reduction that is a complex topic in which students have difficulty, was chosen in the study (Valanides, Nicolaidou, & Eilks, 2003). Firstly, participants were asked to write what they knew about the subject of oxidation and reduction. For this aim, they were asked two questions which did not guide them. They are as follows:

What are the main concepts of the subject of oxidation and reduction?
What is your opinion of the actions based on oxidation and reduction reactions?

The participants answered the questions individually and they were given approximately 30 minutes to answer. Then the answers they gave to the questions were collected, and a flow map for each participant was prepared by the researcher. The sequential flow of participants’ ideas about the subject was represented with linear arrows while the linkages between related ideas were demonstrated with recurrent arrows in the flow map. The recurrent arrows were used in the direction of the ideas that the participants had previously stated. Misconceptions providing information on the accuracy of their cognitive structures were also represented in the flow map.

The reliability of the flow map method. The reliability of the flow map method was secured by consulting a second independent researcher who is an expert in chemistry education and has undertaken studies related to the use of a flow map method to diagram participants’ narratives. Inter-coder agreement for sequential statements was around 0.92, and for recurrent linkages was around 0.88. Since it is considered sufficient for narrative analysis if the reliability is greater than 0.80 (Tsai & Huang, 2001), it can be said that this flow map method was sufficiently reliable for the purpose of this study.

Data Analysis
The flow maps obtained through prospective chemistry teachers’ written narratives were analysed in terms of quantitative variables used in presenting cognitive structures in quantitative statements. The quantitative variables included in the analysis were as follows:

• Extent: The total number of ideas in the flow map (the number of linear linkages),
• Richness (recurrent linkages): The number of recurrent linkages in the flow map,
• Integratedness: Richness / (Extent + Richness),
• Accuracy: The number of misconceptions in the flow map (Tsai, 2001).