XI. Read the new words and memorize them.

     1. to discover-делать открытия, открывать

     2. to arrange-располагать, классифицировать

     3. separate-отдельный

     4. a column-столбик

     5. a series-ряд

     6.weight-вес, масса

     7 to increase-возрастать, увеличивать

     8. across-через

     9. dependence-зависимость

     10. a property-свойство

     11. to construct-создавать

     12. space-место

     13. vacant-пустой, свободный

     14. vacancy-пустота

     15. to consider-полагать, считать

     16. probably-вероятно

     17. an establishment-заведение

     18. to serve-служить, быть полезным

     19. a research-исследовательская работа

 

XII. Match the words from the left column with the equivalents from the right one.

a) 1. vacant                               полагать, считать

     2. property                             вес, масса      

     3. to consider                         столбик

     4. probably                            пустой

     5. dependence                       располагать

     6. weight                               зависимость

     7. serve                                  ряд

     8. column                              служить

     9. to arrange                          свойство

b) 1.через                                  to construct

   2.создавать                           to increase

   3.возрастать                         an establishment

   4.заведение                           across

   5.место                                  vacancy

   6.пустота                               space

XIII. Give Russian equivalents to.

the Periodic law, in tabular form, to bring their correspondences, quite

clearly, a separate column, one horizontal line, the atomic weight, from the left to right, the properties of the elements.

XIV. Give English equivalents to.

разделен на девять групп, в форме таблицы, атомный вес, составлять таблицу, периодический закон, слева на право, в  будущем, открывать закон.

 

XV. Read and translate the text "Mendeleyev's Periodic Law". Do the tasks below.

Mendeleyev's Periodic Law

 The Periodic Law was discovered by D. I. Mendeleyev in 1869. Mendeleyev arranged the elements in tabular form in such a way as to bring their correspondences quite clearly.

 The elements are divided into eight groups, each of which is entered in a separate column. They are also divided into 10 «series» each of which is entered upon one horizontal line. The atomic weights increase across the table from left to the right. D. I. Mendeleyev was the first to discover the law of dependence of the properties of the elements upon their atomic weights. The elements in any one column are similar to one another in many ways, the resemblance being very striking.

 Mendeleyev found it impossible to construct his table without leaving many of the spaces in it vacant. He considered these vacancies to correspond the elements which were not then known, but which would probably be discovered in the future.

 Today the Periodic Law is studied by millions of secondary schoolchildren and by the students at higher establishments of natural sciences and engineering. It is studied by philosophers, historians and teachers.

 The Periodic Law serves as a platform for thousands of researches.

 

XV I. Quote the sentences in which the following words and word-combinations are used in the text and translate them into Russian:

in tabular form, dependence of the properties, a property, an establishment, vacancy.

 

XVII. Compose the sentences using the following word-combinations:

разделен на девять групп, в форме таблицы, периодический закон, атомный вес повышается, составлять таблицу, слева на право, в будущем, открывать закон, зависимость свойств элементов от их атомных масс.

 

XVIII. Find the sentences with Passive Voice in the text and translate them into Russian.Make these sentences negative and interrogative.

 

XIX. Read and translate the following sentences:

In 1893 Mendeleyev was appointed director of the Bureau of Weights and Measures. Much attention was paid to research work in our country. In 1869 Mendeleyev published his Periodic Table of elements which began a new chemical thought.

 

XX. Insert prepositions.

...Tziolkovsky's first book... a metallic dirigible appeared.

Mendeleyev was interested... Tziolkovsky's work and helped him to publish his scientific papers. Tziolkovsky made many parts... his flying machines... his own hands. This great scientist was little known... old Russia.