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Volume 29, Issue 4  (2020)

New Approaches:
M. Karakas
Teaching Phases of the Moon with a Role Play

Full text: PDF (311 K)

K. Ivanova
Model for Using Cloud Technologies in Interdisciplinary Project in Chemistry and Environmental Protection [In Bulgarian]

Full text: PDF (315 K)

Teaching Efficiency:
N.A. Taneva, V. Bozhilov
Comparison of Interactive Methods in Teaching Physics and Astronimy in Grade 10, Level I [In Bulgarian]

Full text: PDF (360 K)

R. Sanjeev, V. Jagannadham
Attenuation Effect in Aliphatic Acids Extended to Alkanes the Carbon Acids via the Aliphatic Alcohols: An Educational Perspective in Chemistry

Full text: PDF (359 K)

K. Shishkoski, V. Zaroska
Jacob's Ladder for the Physics Classroom

Full text: PDF (306 K)

Bulgarian Educational Tradition:
B. V. Toshev
School Chemistry Laboratory: Oxygen Production [In Bulgarian]

Full text: PDF (363 K)

B. V. Toshev
Echo from the Past: The Active School [In Bulgarian]

Full text: PDF (449 K)

From the Research Laboratories:
M. Karami, F. Fathizadeh, A. Yadollahi, M. Aboozari, Y. Rahimian, R.A. Filabadi
Comparative Performance and Digestibility of Nitrients in Afshari and Ghezel Ram Lambs

Full text: PDF (308 K)

Science and Society:
M. Hilali
Aromatic and Medicinal Plants and Their Use of the Massmouda Region Northern Morocco

Full text: PDF (435 K)

R. Tomova, S. Asenova, P. Koseva
Calcium, Phosphorous and Other Factors in the Bone Health [In Bulgarian]

Full text: PDF (341 K)


Khimiya, Volume 29, Issue 4(2020)

Khimiya. 29, 435-444 (2020) Author(s): M. Karakas:

Abstract.This paper provides an example of an innovative science activity applied in a science methods course of 48 future science teachers at a small university in northeastern Turkey. The aim of the activity is to help prospective science teachers understand the phases of the moon in a simple way bay using a role play teaching techniques and see an innovative teaching example implemented by the instructor.

Keywords: phases of Moon; demonstrations and analogies; role play; learning activities; elementary and middle school science


Khimiya. 29, 445-459 (2020) Author(s): K. Ivanova:

Abstract.In the report the author shares an interdisciplinary project that includes the subjects Chemistry and Environmental Protection, Bulgarian Language and Literature, Mathematics and English. The project involved four teachers, 93 students from the 7th grade of the Primary School “Jane Sandanski” in Plovdiv and two assistants from the Faculty of Chemistry at the “Paisii Hilendarski” University of Plovdiv. The collaboration aims to enhance teamwork skills and improve the digital skills of working with Google tools for both students and teachers. The completion of the assignment contributes to the students' future preparation for life, reveals the power of collaboration and the need for knowledge in various scientific fields, which also increases their motivation to seek and find information independently.

Keywords: interdisciplinary project; digital skills; teamwork; G Suite for Education


Khimiya. 29, 460-470 (2020) Author(s): N.A. Taneva, V. Bozhilov:

Abstract.This paper builds on the results of an empirical report prepared in the context of the European project MAR.CH. and a review of the literature on the use of ICT in school. An original study on the role of the teacher in contemporary online (interactive) teaching is presented. The effectiveness of interactive methods for education was analyzed with the help of original online questionnaire. Our results contribute to understanding the effectiveness of interactive education in secondary schools in Bulgaria and Europe, as well. The conclusion is that in online lectures or distance learning via multimedia presentations, it is preferable to have good visualisation of the material. Furthermore, this type of teaching is mostly preferred by the students as a mean for self-training and to research additional information rather than as a primary method for learning new material. The role of the teacher's actual appearance in the videos and multimedia presentations does not seem to be crucial to the teaching of the material. Much more important though are the technical characteristics and the postprocessing of the video, ensuring good visibility of the slides with the material. We also stress that, based on our research, distance learning is generally not preferred as a the principal method for teaching. The results, published here for the first time, have lead to a successful defense of a Master's Thesis at the Faculty of Physics at the Sofia University in July 2016.

Keywords: astronomy; education; STEM; ICT; interactive teaching methods


Khimiya. 29, 471-483 (2020) Author(s): R. Sanjeev, V. Jagannadham:

Abstract.A simple, new, lucid and an improved version of a protocol over Andrew William’s treatment is presented in this article for the evaluation of the attenuation effect of methylene group on the deprotonation process of aliphatic acids RCOOH ⇌ RCOO- + H+ and extended to aliphatic alcohols and alkanes; the carbon acids.

Keywords: attenuation effect; methylene group; aliphatic acid dissociation equilibriums, Taft rho*


Khimiya. 29, 484-487 (2020) Author(s): K. Shishkoski, V. Zaroska:

Abstract.Jacob’s ladder is a relatively simple experiment simultaneously demonstrating the physical effects of gas discharge and buoyancy (Archimedes force) acting on an arch. The goal of the present work is to describe an experimental set-up for the Jacob’s ladder built by high school student and their teacher and meant for the physics classroom in any high school around the world.

Keywords: demonstration experiment; high-school; Jocob’s ladder; gas discharge; Archimedes force


Khimiya. 29, 488-495 (2020) Author(s): B. V. Toshev:

Abstract.Only a real chemical experiment in class can motivate students to study chemistry willingly. In this respect, Bulgaria has a rich educational tradition, which today is completely forgotten. This article shows how oxygen can be produced in a school laboratory. The instructions for this were given by Filip Burmev in 1939.

Keywords: school experiment; school laboratory; oxygen production


Khimiya. 29, 496-504 (2020) Author(s): B. V. Toshev:

Abstract.Bulgaria has a rich educational tradition. Nowadays, this tradition is not known to such an extent as to influence the current state and development of Bulgarian education. This article documents the ideas of the Bulgarian pedagogical specialists from 1937 for the development of new forms of education in the Bulgarian school. Among them is the so called “active school”.

Keywords: educational tradition, active school


Khimiya. 29, 505-514 (2020) Author(s): M. Karami, F. Fathizadeh, A. Yadollahi, M. Aboozari, Y. Rahimian, R.A. Filabadi:

Abstract.This study was investigated to comparative performance and digestibility of nutrients in Afshari and Ghezel ram lambs. In the first trial 30 animals at the age of 5 months (15 Afshari (AF) and 15 Ghezel (GH) ram lambs were randomly allocated to individual pen, in order to determined fattening performance for a period of 90 days. In the second trial 10 animals at the age of 10 months from each ecotype were randomly allocated in individual metabolic cages to determine the in vivo digestibility for 8 days after adaptation period. Data were analyzed in a complete randomized design using the GLM of SAS and the means were compared with Duncan’s multiple range test. The results showed that there wasno significant effect in initial body weight, daily gain, feed conversion ratio and feed efficiency between treatments. Ghezel ram lambs had lower feed intake compared to Afshari ram lambs. The study showed that there were no significant differences for digestibility of DM, protein, EE, ADF, NDF and P, Ca, Mg, Fe and Cu between treatments. In conclusion the results showed that GH had no significance effect on feed digestibility and fattening characteristics of cross breed lambs.

Keywords: ram lambs; Afshari; Ghezel; fattening performance; digestibility


Khimiya. 29, 515-526 (2020) Author(s): M. Hilali:

Abstract.An ethnobotanical study of medicinal and aromatic plants was conducted in the Massmouda district of the northern city of Ouezzane in Morocco. It was done in order to establish the catalog of aromatic and medicinal plants and to gather all the information concerning the therapeutic uses practiced by the local population in the studied area and finally we sensitize the local population to use medicinal aromatic plants in traditional medicine by a more effective scientific method and preserve nature. After representation of the region, the survey was carried out according to a probabilistic (random) sampling method during the months of January, February and March 2019, among the inhabitants of five douars distributed in the region of Massmouda. Samples of 20 people are trained for each of the douars (10 women and 10 men for each doaur). The questionnaire concerning subjects such as sex, age, educational level, family situation, profession as well as the mode of use, therapeutic and traditional local applications of aromatic and medicinal plants in the Massmouda region. The results obtained made it possible to inventory 21 exploited species, divided into 14 families. Cataloged plants are used for several purposes, with therapeutic use being the most common (90% of total uses). A very important part of the recipes is recommended for the treatment of certain disorders of the digestive system, the nervous system and the cutaneous system. The leaves and the seed are the most used organ. The most frequently used methods of preparation for most remedies are decoction (38%), infusion (25.5%) and finally powder (25%). The ethnobotanical research carried out in the region of Massmouda regarding traditional use of medicinal plants still persists in the said region it is necessary to do other similar works, in the same area of study, will help us to discover other unknown species, to evaluate the risks associated with the use of certain toxic plants and to adopt a new management approach for safeguarding and preserving natural resources.

Keywords: aromatic and medicinal plant; traditional medicine; herbal medicine; Massmouda


Khimiya. 29, 527-540 (2020) Author(s): R. Tomova, S. Asenova, P. Koseva:

Abstract.In the present study is discussed the physiological role of some biogeneous elements and radicals determining the structure of the bones, studied in the high school course of Chemistry and Environmental Protection. The concept of oxidative stress, caused by free radicals, either produced in the body or introduced to it, is discussed in this paper, adding to the idea of natural antioxidants. Factors increasing the oxidative stress, accelerating the osteoporosis and changing the concentration of calcium, phosphorous, magnesium, copper and zinc are described. The involving of this topic in the syllabus will raise the medical knowledge of students. It will help the formation of healthy habits in the coming generation. This information will help younger people to live a healthy lifestyle, and to prevent osteoporosis in the elderly. This task corresponds with the state health policy. It will also motivated students to study chemistry.

Keywords: osteoporosis; calcium; free radicals; oxidative stress; education


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