Learning and teaching chemistry at lower-secondary school (Doctoral thesis)
In this thesis, we investigate whether (Greek) 8th-grade students are familiar with atoms, molecules, chemical symbols and their model representations, and whether they have understood the concept of the chemical reaction. In addition, we examine the effect of a teaching intervention, in which chemical reactions were taught after the introduction of the concepts of atoms, molecules, and their symbolism. (According to the Greek curriculum, students are introduced first, in macroscopically reactions, then, comes the atom, the molecule and their symbolism, and, after these follow the representation of reactions with chemical equations/with symbols or models.) Finally, we carried out an analysis of the illustrations (the pictures) and the hyperlinks of the interactive (Greek) lower-secondary chemistry books of the so-called "Digital School". For the evaluation of the students, we devised and applied a test and an exam, while the statistical analysis was carried out by using SPSS 23 and EXCEL. According to the findings, and regardless of the teaching intervention, poor-performing students transfer more easily from the symbolic to the submicroscopic level, while no such difference was detected for the relatively high-performing students. With regard to the teaching intervention, no statistically significant difference was detected in the test for the total sample of students between experimental and control groups. Moreover, in four groups of students, of low, moderate, good and high performance, we identified superiority of the experimental group only for the good-performing group (13≤mean<16). Regardless of the teaching intervention, the performance of students in the exam was low (7.11/20). The majority of students did not understand the concept of reaction: 37% of them provided a nearly acceptable definition, while less than 2% gave a full definition. They explained more easily the amount of water produced from a non-stoichiometric ratio of hydrogen and oxygen, in relation to the explanation of the change in carbon mass during its combustion or in iron mass during its oxidation. Also, there was a statistically significant difference in favor of the explanation of the change in the iron mass during its oxidation, relative to the change in carbon mass during its combustion. Regarding the teaching intervention, no statistically significant difference was found in the exam for the total sample between experimental and control groups. However, both the test and the exam showed the trend of experimental groups to have better respond than the control groups. Finally, the 255 illustrations/images in the interactive 8th–grade books were identified as: 61.96% macroscopic, 27.06% symbolic, 3.92% submicroscopic, 6.67% multiple, 0.39% hybrid, and 0% mixed. The corresponding figures for the 233 images of the 9th-grade book were: 47.21, 33.91, 4.72, 13.30, 0.86 and 0%. Finally, only a few hyperlinks in chemistry book of G. Gymnasium lead in connecting three chemical levels.
|Alternative title / Subtitle:||πότε πρέπει να εισαχθεί η ατομική και μοριακή θεωρία;|
when the atomic and molecular theory should be introduced?
|Institution and School/Department of submitter:||Πανεπιστήμιο Ιωαννίνων. Σχολή Θετικών Επιστημών. Τμήμα Χημείας|
|Subject classification:||Χημεία -- Μελέτη και διδασκαλία (Δευτεροβάθμια)|
|Keywords:||Χημεία γυμνασίου,Χημική αντίδραση,Χημική εξίσωση,Χημικά σύμβολα,Προσομοιώματα ατόμων και μορίων|
|Appears in Collections:||Διδακτορικές Διατριβές|
Files in This Item:
There are no files associated with this item.
Please use this identifier to cite or link to this item:This item is a favorite for 0 people.
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.