D. I. MENDELEYEV
I. Study the list of topical vocabulary to avoid the difficulties in understanding the text in exercise V. Consult the dictionary to pronounce the words correctly.
arrange
award
calculation
combine ,
consist of
degree
determine
be engaged in smth -
enormous
enter smth (.) -
graduate (from)
immense
lecture on
obtain
predict
property
synthesize
thesis
weight ,
II. Translate the following constructions, words and word combinations into Russian. Define the part of speech of the words ranked singly. Make up sentences using these words.
Both and , soon, apart from, thanks to, later, besides, to take into account, as well (as), in honour of, at that time, in memory of.
III. Consult the dictionary and write down all the meanings of the following nouns. Make up word combinations with them.
Significance, value, amount, increase, investigation, research.
IV. Read and translate the sentences paying attention to the word result used as noun or verb.
| result n as a result result v result in (-), (-) result from (-) |
1. The results of our experiments are published in a scientific journal.
2. A chemical equation shows what substances react and what product results.
3. The reaction of zinc with this acid results in the replacement of hydrogen atoms in the acid by zinc.
4. Numerous experiments resulted in the discovery of a new radioactive element.
5. As a result of these collisions new radioactive elements are formed.
6. Transformation of some elements results in a release of atomic energy.
7. The physical changes in the substance resulted from heating it.
V. Read and translate the text from English into Russian.
D. I. MENDELEYEV
(1834 1907)
D. I. Mendeleyev is an outstanding Russian scientist. He was born in Tobolsk in 1834. In 1850 at the age of 16 he entered the Pedagogical Institute in Petersburg to study chemistry. Five years later he graduated from it with a gold medal. He was invited to lecture on theoretical and organic chemistry at Petersburg University.
To continue his studies and investigations Mendeleyev went to Germany in 1859. While living abroad, he made a number of important investigations.
In 1965 Mendeleyev was awarded the Doctor of Science degree for the thesis on the combination of alcohol with water. This work was both of great theoretical and practical significance. Soon after that D. I. Mendeleyev was appointed Professor of General Chemistry of St. Petersburg University. Apart from lectures and supervision of the laboratory Mendeleyev carried out great research work.
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In the year 1868 D. I. Mendeleyev started a very significant work Fundamentals of Chemistry. When working on the subject, he analyzed an enormous amount of literature, made thousands of experiments and calculations. This immense work resulted in the Table of Elements. The Table consisted of vertical groups and horizontal periods. Mendeleyev suggested a system of classification in which the elements were arranged in the order of increasing atomic weights. The main idea of the Periodic System is a periodic repetition of the properties of elements with the increase of their atomic weights.
To arrange all the existing elements in the table Mendeleyev had to overcome colossal difficulties, because a considerable number of elements were unknown at that time and the atomic weights of 9 elements (out of 63) were wrongly determined.
Thanks to these investigations Mendeleyev was able to predict not only the existence of a few unknown elements but their properties as well. Later these elements were discovered.
D. I. Mendeleyev was engaged not only in the study of chemistry. Combining theory with practical activity he carried out enormous research in coal, petroleum, iron and steel industries in Russia.
Mendeleyev died in 1907 at the age of 73.
The achievements in chemistry and physics at the end of the 19th and at the beginning of the 20th century made it necessary to reconstruct the Periodic Table taking into account new discoveries. This progress resulted in the discovery of the inert gases and the study of 14 rare earth elements. Besides, 11 new radioactive elements were obtained. Two of them were named in honour of Russian scientists: the 101st was called Mendelevium and 104th Kurchatovium (in memory of Igor Kurchatov).
The 114th element in the Mendeleyevs Periodic Table has now been found. The element has the atomic weight of 289. The 114th was predicted by theoretical physicists and has been synthesized by a group of researchers with Professor Yury Oganesyan at the head. It was done at the Flerov Laboratory of Nuclear Reactions in Dubna.
So, Mendeleyevs Periodic Law opened a new era in the history of chemistry. After more than 100 years of its existence the Periodic Law has completely preserved its value.
