Chemistry Reference
In-Depth Information
Chapter 10
Structure-Oriented Approach
in Chemical Education
Chemists consider the chemical structure to be very important and essential for the
understanding of substances and their properties; for them, the structure of matter is
of highest significance. Modern chemistry lessons should therefore integrate exem-
plary chemical structures and the use of corresponding structural models. Following
these preliminary considerations we will develop and describe a conception, which
is called “structure-oriented chemistry.”
10.1 Chemical Structures in Modern Chemistry
Today's chemists are mostly interested in the chemical structure for explaining the
properties of produced substances or for the development of new substances. The
newest edition of the German “GDCh-Nachrichten aus der Chemie” [
1
] shows an
example (see Fig.
10.1
): “Lithium-organyl compounds are mostly regarded as
monomers - but the real structure is more sophisticated. Taking the example of
methyl lithium, one observes that it is insoluble in nonpolar solvents like pentane or
hexane. An explanation may be the structure of tetramers like (MeLi)
4
; they consist
of Li-tetrahedrons whose faces are occupied by methyl groups. The Li-C forces
knot those tetrahedrons together and create a three-dimensional network. That is the
reason for insolubility of lithium organyl compounds in nonpolar solvents.” [
1
]
The reader should know that in publications of inorganic or organic chemistry
every structure of a new crystalline substance or molecule is generally illustrated by
model drawings and discussed (see Fig.
10.1
). If students are supposed to get an
insight into procedures of today's chemists, they should have the chance to reflect
on structures of specially chosen substances in their chemistry lessons. The under-
standing of the structure of matter and the regrouping of atoms, ions, or molecules
in reactions can be developed on the base of Daltons atomic model. Chemical
symbols for the composition of substances and equations can be derived from
chemical structures. These approaches would represent modern chemistry lessons
because they connect to fundamental ideas of today's scientists. Later in their
