Volume 16, Issue 1  (2007)

Editorial:
B.V. Toshev. Bulgarian Education in the European Educational Area Full text: PDF (148 K)	3
Curriculum Matters:
E. Boiadjieva, D. Lazarov. Educational Goals and State Core Curricula Requirements Full text: PDF (124 K)	10
Teaching Chemical Experiment:
V.M. Petrusevski, M. Bukleski, M. Stojanovska. The Economic Demonstrator: Prepare It Once, Use It Many Times. II. Continuous Thermochromism in Aqueous Solutions of Transition Metal Chlorides Full text: PDF (152 K)	20
Problems:
A. Tafrova-Grigorova A Study of the Test for the 8th National Chemistry and Environmental Protection Competition - Lovech 2006	29
Advanced Chemistry:
H. Daiev, L.-A. Daieva Chemical Species in the Environment	52
History and Philosophy of Chemistry:
T. Christofilis, M. Kousathana Historical Models of Chemical Kinetics in Science Education	61
Guide for Authors:
	76
Khimiya, Volume 16, Issue 1 (2007) Khimiya. 16, 3-0 (2007) Author(s): B.V. Toshev.: Abstract. On January, 1st, 2007 Bulgaria became a regular member of the European Union. Thus Bulgaria’s educational system became a part of the European educational area. The article emphasizes on some special problems that have not been solved yet: i) the need of balance between the processes of learning and breeding within the Bulgarian school; without this balance the socialization of youth as a fundamental educational goal can not be achieved; ii) the problem of the modern training of the prospective teachers and as well as the problem of their continuing education; iii) the need of structural and conceptual changes in the Bulgarian pedagogical academia after establishing the Science of Education by a process of amalgamation of the separate pedagogical disciplines (pedagogy, didactics, educational psychology, philosophy of education, etc.). top Khimiya. 16, 10- (2007) Author(s): E. Boiadjieva, D. Lazarov.: Abstract. A central goal of the standard movement has been to help all pupils learn challenging content. The standard-based approach (1990’s) has its projections in Bulgaria as state core curricula requirements. Neither its authorship nor its approvement in practice have ever been discussed professionally. The present paper emphasizes on the relationship between the educational goals and the state core curricula requirements. The state core curricula requirements should be considered as a concise professional presentation of the educational goals. All the parties of the educational process – pupils, teachers, parents and education policy-makers should be acquainted in details with these requirements. Otherwise the motivation of pupils to participate actively in the process in learning would be put in question, and, therefore, the educational goals would not be achieved. top Khimiya. 16, 20- (2007) Author(s): V.M. Petrusevski, M. Bukleski, M. Stojanovska.: Abstract. Continuous thermochromism was studied in systems containing metal chlorides and diluted hydrochloric acid. Most of the divalent and trivalent transition metal chlorides were included. The color changes may vary from barely visible (e.g. in MnCl2–HCl–H2O), through visible (e.g. in NiCl2–HCl–H2O) to remarkable (e.g. in MoCl3–HCl–H2O). Well known examples of CoCl2–HCl–H2O and CuCl2–HCl–H2O were also included. The color changes were ascribed (as has been done many times earlier) to changes in the coordination sphere of the metal cations. The solutions were sealed in pairs of glass ampoules, thus offering the possibility to use the samples unlimited number of times. top Khimiya. 16, 29-0 (2007) Author(s): A. Tafrova-Grigorova: Abstract. The National Competition Chemistry and Environmental Protection Test performed by 189 secondary school students in 2006 is presented. It consists of two different format parts: a first part containing 50 multiple-choice items and a second part including 20 constructed response items. The test, being designed and scored by a National Commission appointed by the Ministry of Education and Science, is recognized by a lot of Bulgarian Universities as a university admissions entrance test. The features of the test are studied and compared to those of the previous year test. Both parts of the test have a high reliability and a great number of good quality items but differ in their overall difficulty. There is a strong correlation between Part I and Part II student performance. The most difficult and the easiest items are outlined and discussed. Difficulties to solve problems involving calculations persist. top Khimiya. 16, 52-0 (2007) Author(s): H. Daiev, L.-A. Daieva: Abstract. Chemical species represented by combinations of different forms of elements and compounds take large place in the processes occurring in the environment. The historical development of the term species has been followed, starting with its Latin origin, going on to its theological and chemical meanings and reaching the recent creation of its derivative "speciation", signifying determination, respectively distribution of species. Some typical species of mercury, arsenic, tin, iron, selenium, zinc, copper, nickel, lead and aluminum have been discussed. It is shown that they differ from the corresponding single forms not only in composition but also in their analytical, kinetic and toxicological behaviors. The speciation analysis methods are applicable as well as for species so as for single forms because the latter can be treated as particular case in respect to the combinations of forms. top Khimiya. 16, 61-0 (2007) Author(s): T. Christofilis, M. Kousathana: Abstract. Reality shapes theory and conversely modifications of theory change and extend our knowledge about reality. Model in science corresponds to a phenomenon, an entity or a process, while at the same time providing an explanation of reality through the theory. Models can be classified in several ways. The emphasis in science education has been gradually shifting toward a greater concern with an overall understanding of science and of its role in society. Models provide a generalization of reality through theory. The delineation of each particular model in the historical sequence of models that represent the development of the study of chemical kinetics, illustrates the dynamism of the process of scientific knowledge. School knowledge in Greece and in other countries is consisted of hybrid models, which falsify scientific knowledge. Students are led to have confusions and misconceptions. Moreover, hybrid models do not help students to understand either scientific reasoning or the process of the development of knowledge and the progress of science. top