Khimiya. 14, 15-24 (2005):
Abstract. Alkali metals form the group 1 of the periodic table, characterized by their
ability to give up one electron to reach the electron configuration of a noble gas.
Halogens form a family of elements in the periodic table that have seven valence
electrons. Two ways of teaching these groups in the 7th class are proposed. In the version
A the order of teaching is as follows: Na, NaOH, experiments on basic hydroxides, Na2O,
alkali group, Cl2, I2, HCl, hydrochloric acid, halogen oxides, summary. In the version B
the order of teaching is as follows: Na. NaOH, Na2O, summary, Cl2, HCl, hydrochloric acid,
halogen oxides, summary, stoichiometry, problems. By educational research the advantage of
the version A is proved.
References: 5
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Khimiya. 14, 25-36 (2005):
Abstract. Organic Chemistry is a challenging subject and students often fail to perform
well in it. Both students and instructors have their own views about Organic Chemistry
teaching and learning. The study describes the perception of Organic Chemistry instructors
from different universities in the SADC (Southern African Development Community) region on
the performance of students in this subject. They have perceived factors such as
conducting tutorials, laboratory sessions, and students’ prior knowledge of the subject
as contributing to students’ success in Organic Chemistry whereas the presence of
anxiety/phobia and time constraint contribute to their underperformance. The study reveals
that the most popular method of instruction is lecture method using chalk and board
followed by demonstration method using models. The suggestions of instructors how to
improve Organic Chemistry teaching and learning are also described.
References: 24
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Khimiya. 14, 37-50 (2005):
Abstract. The behavior of the thioamides as ligands is a subject of the present review.
The literature over the coordination ability of the thioamides and thioamide containing
compounds like thiocarbamides, thiosemicarbazides endothiopeptides and heterocylic thiones
has been reviewed. There are proofs that thioamides coordinate by three ways: as
monodendate ligand by S-atom; as bidendate ligand, by S and N-atoms; and by the same
atoms, but after the deprotonation of the group.
References: 59
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Khimiya. 14, 51-74 (2005):
Abstract. Scientists occasionally find novelties during either their experimental or their
theoretical work. In a number of cases, these results were not totally welcomed or were
considered unimportant. Their discoverers sometimes experienced difficult periods as a
result of the indifference towards their findings. While the discoverer needs to prove a
new result in order to sustain it, the opponents need to present a convincing arguments in
order to reject it. An open mind and respect should always be given to new and unusual
ideas. Numerous examples of such situations are presented.
References: 33
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