Problems in Teaching the Topic of Redox Reactions: Actions and Conceptions of Chemistry Teachers

Abstract

Although there is growing interest in studies of teachers' actions and conceptions, little is known about content-related teaching problems arising in science classrooms. This article presents a case study of problems which can occur when teaching the topic of redox reactions to Grade 11 students. Two chemistry teachers, a senior and a junior teacher, were involved in the study. Their reflective comments on the teaching problems were also investigated. Research data were obtained from classroom observations and audiotaped recordings of classroom practice. After the lessons, we conducted semistructured interviews with the teachers. The teaching problems are reported in terms of teaching activities causing difficulties for students in considering new conceptions to be necessary, intelligible, plausible, or fruitful. Analyses of the teachers' comments on these teaching activities clarifies a number of reasons why they acted as they did. It can be concluded that teachers' scientific expertise is an important source of difficulties when teaching redox reactions. Implications for an improvement of current chemistry classroom practice and contentrelated teacher training are offered.

Identification of Chemistry Learning Problems Viewed from Conceptual Change Model

“…The results of the study above confirmed previous findings related to misconceptions (de Jong, 1982;de Jong et al, 1995;Nahum, Hofstein, Mamlok-Naaman, & Bar-Dove, 2004;Chiu, 2005;Barke, Hazari, & Yitbarek, 2009). The students' misconceptions were found on almost all chemistry topics, such as atomic structures, periodic systems, and chemical bonds (Redhana & Kirna, 2004).…”

“…The teacher-centered teaching that emphasizes the calculation aspects enables low comprehension and misconceptions among students. de Jong et al (1995) reported that, in fact, the chemistry teachers who taught redox reactions had a lot of learning problems related to the conceptual change model. These learning problems included they presented the unsuitable problems, presented the unnecessary explanations, explained the conceptions prematurely, used the confusing terms, taught the less context, ignored the alternative conceptions of students, discussed the less application of concepts (especially in industry), and explained too many procedures from experts.…”

“…The studies involving the students' misconceptions in relation to the conceptual change model has been reported on the electrochemical concept in the Netherlands (de Jong et al, 1995). These studies were forwarded to other countries, such as the United Kingdom (Bojczuk, 1982), the North America (Finley et al, 1982), and Australia (Butts & Smith, 1981).…”

The Insidious Nature of ‘Hard‐Core’ Alternative Conceptions: Implications for the constructivist research programme of patterns in high school students’ and pre‐service teachers’ thinking about ionisation energy

“…A range of studies report subject knowledge deficiencies among trainee teachers ('pre-service' teachers), for example in astronomy (Trumper, 2001); matter conservation (Haidar, 1997); chemical equilibrium (Quilez-Pardo & Solaz-Portoles, 1995), redox reactions (De Jong, Acampo, & Verdonk, 1995), and behaviour of gases (Lin, Cheng, & Lawrenz, 2000). It seems likely that teachers' own alternative conceptions themselves make up one significant factor in the development of some alternative conceptions among students, and so an important focus of the constructivist RP should be the characteristics of alternative conceptions which remain unchallenged by degree level study and initial teacher education courses, and may be actually presented as target knowledge in science teaching.…”

Redox models in chemistry textbooks for the upper secondary school: friend or foe?

“…As mentioned above, redox reactions are perceived to be one of the most difficult areas both to learn (de Jong and Treagust, 2002) and to teach (de Jong et al, 1995). Three important difficulties that students have are: 1) difficulties in comprehending oxidation and reduction as complementary reactions (de Jong and Treagust, 2002); 2) difficulties in identifying oxidizing and reducing agents (imprecise terminology and complex language use) (de Jong and Treagust, 2002); 3) the comprehension that a redox reaction is defined as a loss and a gain of oxygen (Garnett and Treagust, 1992;Schmidt 1997;Österlund and Ekborg, 2009).…”