Determining the pre-service teachers’ perceptions of atom and atomic structure through word association test

In the current study, it was revealed that the pre-service teachers wrote fewer propositions after they had taken the modern physics course; yet, the ratio of the correct propositions increased. This might indicate that in the understanding of the concepts involved in the subject “Atom and Atomic Structure”, modern physics courses are effective. The reasons for the low ratio of the correct prepositions might be the superficial knowledge of the pre-service teachers about the subject of “Atom and Atomic Structure”. At the beginning of the term, students’ superficial learning should be determined and then the required precautions should be taken to prevent them from being permanent.

The subject of “Atom and Atomic Structure” includes many abstract concepts. When the pre-service teachers’ mind maps were examined, it was seen that the pre-service teachers associated the concepts with each other; yet, they could not express the relationships correctly. It has been revealed that the pre-service teachers have some mislearnings and misconceptions on the subject of “Atom and Atomic Structure”. This finding concurs with the findings reported by Ercan et al. (2010), Kurt et al. (2013) and Aydemir (2014) in the literature. By developing new methods and using alternative methods, “meaningful and deep learning” and “information network” should be able to be measured with correct techniques (Ercan et al., 2010). The use of analogies in the teaching of abstract concepts such as atom, molecule and chemical bond can make it easier for students to understand and perceive these concepts (Harrison & Treagust, 2000). This shows that the use of analogies during the instructional process may help students learn concepts correctly.

As a result of the current study, it was found that while the number of correct prepositions written for the key concepts of “Electron” and “Orbit” was decreasing, the number of the correct prepositions written for some key concepts such as “Spin, Quark, Neutron and Nucleus” increased. This might indicate that the pre-service teachers’ perceptions of some special concepts related to the subject of “Atom and Atomic Structure” such as “Spin, Quark” developed after they had taken the modern physics course. It was also found that the pre-service teachers attempted to write more prepositions for the concepts of “Electron, Proton, Neutron and Nucleus”, which had been known by the pre-service teachers from elementary school, yet their prepositions were wrong to a great extent. This might indicate that the pre-service teachers associated the concepts they knew more easily but they did not correctly perceive even these concepts.

When the results related to the pre-service teachers’ mind maps were examined, the first association seen was between the key concept of “Atom” and “structural unit”. This is believed to be a result of the fact that the pre-service teachers have been taught with the textbooks defining atom as the building block since elementary school (Akyol, 2009) and in the curriculum, atom is defined as the structural unit (MEB, 2013). Similarly, Niaz (1998) and Justi & Gilbert, (2000) stated that students’ misunderstandings about the key aspects of the quantum mechanics model of atom result from the figures and explanations given in textbooks about atomic models. Tsaparlis & Papaphotis (2009) argue that in the atom models in students’ minds, the most commonly encountered model is the Bohr atomic model and this can be because this model is widely included in curriculums and textbooks. Moreover, the pre-service teachers’ association of Proton with the Nucleus might be because of the atom weight calculations frequently used in general chemistry courses. In the mind maps prepared after the completion of the modern physics course, it is remarkable that the pre-service teachers established the relationship between “Electron” and “Orbit”. This might be an indicator of the pre-service teachers’ attempt to locate the electron in their minds while constructing a model for the atom. Studies in the literature conducted at different age levels (Özmen, 2005; Akyol, 2009; Tsaparlis & Papaphotis 2009; Çökelez & Yalçın, 2012; Yaseen & Akaygün, 2016) show that the atomic model in the individuals’ minds is generally the Bohr Atomic Model. The model showing that there is an electron at an orbit around the nucleus is an indication of individuals’ effort to locate the electron.

In their mind maps, the pre-service teachers first included the concept of “Nucleus” in their expressions of the atomic models. This is believed to be because of the importance attached to nucleus in the teaching of atomic models as of the elementary education. Moreover, the pre-service teachers were determined to be able to establish the structures making up atom such as electron, proton and neutron and the relationships related to their charges. This might be the result of the calculations made by using the charges of particles in chemistry and physics courses. In light of the mind maps derived from the findings of the current study, it was concluded that the general chemistry and physics courses had constructed the perception of structural unit in relation to the concept of atom in the students. After the completion of the modern physics course, the concept of atom created the perception of subatomic particles. In a similar manner, in the mind maps generated after the modern physics course, the concepts of electron and orbital were associated earlier. This is believed to be because the modern physics course taught the micro world. This might indicate that modern physics classes introduce students to the micro world and create the perception of the breakability of atom in students. After getting introduced to the micro world, it is seen that instead of orbit, the students started to use orbital to locate the electron. This might be because the students started to perceive the thinking style unique to the quantum world (Şen, 2002) and the relative nature of modern physics.

In their study, Eryılmaz & Ucer (2018a, b) found that the secondary school students stated that they had gained their misunderstandings about atom in different courses and from different teachers. From elementary education, abstract concepts that students experience difficulty in understanding at every level of education should be corrected and students’ knowledge about science concepts should be determined in different courses before starting the course. However, learning continues without detecting the prior knowledge of students and without correcting their misinformation and misconceptions. This can also explain why most of the prior knowledge expressed by the pre-service teachers in the current study were wrong. As a result, the visuals used in textbooks to teach the concept of atom to students should be selected so that they can reflect the correct information about atom. Teachers should emphasize how scientific knowledge about atom has changed throughout the history of science. Students’ prior knowledge should be determined at the beginning of the term and how permanent the learning occurring during the term should be tested at the end of the term by using various techniques such as WAT.