In this paper, we define flip teaching as a curricular platform that uses various strategies, tools, and pedagogies to engage learners in self-directed learning outside the classroom before face-to-face meetings with teachers in the classroom. With this understanding, we adopted flip teaching in the design and enactment of one Year 1 and one Year 2 undergraduate chemistry laboratory session at a higher education institution. The undergraduates viewed videos demonstrating the practical procedures and answered pre-laboratory questions posted on the institution's mobile device application before the laboratory lessons. Analyses of the lesson videos, interviews with the undergraduates and instructors, and undergraduate artefacts showed that the undergraduates had developed a better understanding of the theory undergirding the procedures before they performed the practical, and were able to decipher the complex practical procedures. They also experienced less anxiety about the complex practical steps and setup, and subsequently, improved work efficiency. The findings of this study have implications for chemistry educators looking for ways to improve on the design and enactment of the laboratory curriculum to enhance the undergraduates' self-directed learning.

This article describes the development and application of a two-tier multiple choice diagnostic instrument to assess high school students' understanding of inorganic chemistry qualitative analysis. The development of the diagnostic instrument was guided by the framework outlined by Treagust. The instrument was administered to 915 Grade 10 students (15 to 17 years old) from 11 schools after they had learned the theory involved in qualitative analysis and after a series of qualitative analysis practical sessions. The Cronbach alpha reliability of the instrument was .68, the facility indices ranged from .17 to .48, and the discrimination indices ranged from .20 to .53. The study showed that the Grade 10 students had dif®culty understanding the reactions involved in the identi®cation of cations and anions, for example, double decomposition reactions, the formation and reaction of complex salts, and thermal decomposition. The ®ndings of the study and literature on practical work were used to develop a qualitative analysis teaching package. ß

The topic of ionisation energy is important as the concepts involved provide the foundation for the understanding of atomic structure, periodic trends and energetics of reactions. Previous research has shown that A-level (high school) students in the United Kingdom had difficulty understanding the concepts involved in ionisation energy. This paper describes the development and administration of a two-tier, multiple-choice instrument on ionisation energy, the Ionisation Energy Diagnostic Instrument, to determine if A-level students (Grade 11 and 12, 17 to 18 years old) in Singapore have similar alternative conceptions to those of their counterparts in the United Kingdom, as well as explore their understanding of the trend of ionisation energies across Period 3. The items in such instruments are specifically designed to identify alternative conceptions and misunderstandings in a limited and clearly defined content area. The results showed that students in Singapore applied the same octet rule framework and conservation of force thinking to explain the factors influencing ionisation energy as the students in the United Kingdom. In addition to the above alternative frameworks, many students in Singapore also resorted to relation-based reasoning to explain the trend of ionisation energies across Period 3 elements. [Chem.

Tan. 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.. AbstractThe present study contributes to the constructivist research programme (RP) into learning science by comparing patterns in responses from two groups of learnerssenior high schools students and pre-service teachers -in the same educational context (Singapore), to a diagnostic instrument relating to the topic of ionisation energies. This topic is currently included in the curriculum for 16-19 year-old students studying chemistry in Singapore (and elsewhere). The comparison shows that although (a) graduate pre-service teachers offered some types of incorrect responses less frequently than high school students; (b) they retained high levels of alternative conceptions commonly found among high school students; and -of particular note -(c) certain alternative conceptions were found to be more common among the graduates. This suggest the intuitive appeal of certain alternative conceptions is such that they can readily be reproduced down 'generations' of learners. The findings are explored in terms of a range of conceptual resources that have been developed within the constructivist RP. The analysis suggests that the curriculum sets out inappropriate target knowledge for senior high school students, given the nature of the subject matter and the prior learning of the students. It is also suggested that it may be fruitful to consider conceptual learning in terms analogous to the RP found in science, and that from this perspective certain insidious alternative conceptions can be understood as derived from commitments that are taken-for-granted and protected from explicit challenge by a protective belt of refutable auxiliary conceptions.