The most difficult concepts in Chemistry-1 as perceived by Lycee-II students and their level of understanding of those cencepts

The aim of this study is to find out the most difficult concepts in Chemistry- 1 as per ceived by Lycee-2 students and examine their level of understanding of those concepts. This study consists of three sections. In the first section a questionnaire was deve loped based on a pilot study to find out students' perceptions of the most difficult concepts in Chemistry- 1 textbook. This questionnaire was implemented to 93 students from two different Lycees (School A and B). In the second part of the study, an achievement test on the same concept was developed and implemented to the same sample of students. Beside these (implementation of questionnaire and test) informal interviews were undertaken by both the teachers and students in the two Lycees. In the last part of the study the collected data was analysed. In summary the following results were found. 1. In school A, the most difficult concept was the relationship between presure-tem- parature in gases. In school B, the most difficult concept was positron radiation. 2. The level of understanding was the lowest in School A and B in the topics related to Radioactivity. 3. The results of the questionnaire and the test are not fully matched. In some cases, the results are quite opposite. Based on the findings of this study some suggestions are made to improve the quality of Chemistry education in Lycees Key Words: Chemistry teaching, concept development, difficult chemical concepts VI