TOPICS SUGGESTED FOR DISCUSSIO1 (Экзамен по английскому языку), страница 2

As far as I understand it green chemistry is a design and sometimes redesign of reaction processes in order to minimize waste, reduce risk and make the processes themselves safe for the chemists. There are no doubts that green chemistry is important everywhere but it is especially important in synthetic organic chemistry where a large number of corrosive, and toxic chemicals are used. Here we should think about using some eco-friendly techniques which are supposed not only to improve the results of reactions but also to bring down the cost of waste disposal at the end of a chemical process. On the other hand, the engineering concepts that prevent pollution and offer zero waste in laboratories and factories should be worked out and immediately implemented.

I have heard of an Englishman who built (or maybe sculpted rather) his house out of the mixture of sand, clay and gravel because he thought that it was important to keep everything as natural as possible. And now his house can breathe and birds use it as a place for building their own houses - their nests. Of course it is a funny story. But this is the example of how an eco-technique works. Some steps towards environment friendly chemistry have also been made. Though I think that they still remain to be more theoretical than practical, that is – those techniques don’t work, they are merely written on paper. To illustrate my point I can tell a few words about the latest research on bioremediation.

Bioremediation processes are considered to be low-cost, eco-friendly methods to make water decontamination less difficult, particularly for small towns and villages. The unexploited sorption properties of the powdered seed of the plant Moringa oleifera (SMOS) for the removal of Arsenic [As(III) and As(V)] from aqueous solutions became known not long ago. Protein/Amino acid–Arsenic interactions are found to play an important role in the biosorption process using plant biomass SMOS.

If we are able to find methods to make science (chemistry first of all), as well as industry and even our everyday activities as environment friendly as possible we shall have a hope for the future life on the earth. And we, chemists, should remember that it is our task to prolong the life of the humanity and that green chemistry is not an ideal, unrealistic chemistry. It is just what chemistry must be.

Topic 6. The Most Important Discovery in Chemistry

I think that one of the most important discoveries in chemistry is the discovery of benzene structure. Faraday was the first to isolate this compound in the beginning of the nineteenth century. Nevertheless, during more than 100 years since that moment scientists could not explain its properties. The composition of this substance was established rather quickly, it was found that benzene was very unsaturated hydrocarbon. However, its chemical inertness refuted this theory. Then Kekule supposed the cyclic structure with single and double bonds. However, it could not explain all properties of benzene too. The real structure of benzene was discovered only in the beginning of the twentieth century. It was found, that six electrons are distributed between six carbon atoms. This discovery allowed chemists to describe structure of the big class of the organic compounds called aromatic hydrocarbons or arenes. And during that researches on the benzene structure chemists discovered resonant structures of different organic substances, created the theory of chemical bond and made number of other important discoveries which forced the development of different branches of chemistry, especially in organic chemistry and in physical chemistry. We can even say that researches on the benzene structure laid the foundations for modern theoretical organic chemistry.