Complete the sentences below with words from the box.



hardship                 enroll          resign         appoint                   confirmed              resulted

solution                  expand       density       uniform

1. They are going to ... a new professor in the Chemistry department.

2. Many famous people in the past suffered a lot of … to achieve their goals.

3. The experiment proved that the gases had a … reaction, that is the same reaction.

4. Most schools expect you to … before you begin your studies.

5. The … of a substance is how thick and compact it is.

6. If metal is heated you will see it … .

7. It was a … made up of water and salt.

8. If somebody is unhappy in their job, they may … .

9. The experiment in the lab … in a huge explosion.

10. The outcome of the experiment … his theory.

Dmitri Mendeleev

Dmitri Ivanovich Mendeleev was born in Tobolsk, in Siberia, on 7 February, 1834. As a child he showed a great interest in Mathematics and Physics and was a talented student. Despite the hardships experienced by his family while he was growing up, his mother was determined to see him educated and to help him achieve his dreams. After the family moved to St Petersburg, she managed to enroll him as a student science teacher on a full scholarship. Despite many more problems, Mendeleev earned his decrees and eventually, in 1863, was appointed Professor of Chemistry at the Technological Institute and the University of St Petersburg.

Probably his greatest scientific achievement was the discovery of the periodic law and the development of the periodic table of elements. He left gaps in his table for undiscovered elements and predicted the properties of the elements that would fit these gaps. His predictions were confirmed when, during his lifetime, three predicted elements; gallium, germanium and scandium, which he had named eka-aluminium, eka-silicon and eka-boron respectively, were discovered. These discoveries gave him threat respect among members of the scientific community.

However, Mendeleev' made other important contributions to science. He was involved in many areas including hydrodynamics, agricultural chemistry, mineral recovery, meteorology and chemical technology. One particular contribution involved solutions, lie spent a lot of time studying how the nature of solutions could be determined, adding greatly to our understanding in that field. In addition, he was involved in physical chemistry, looking at the expansion of liquids because of heat. He spent time in Paris with Henri Victor Regnault studying the densities of leases and came up with a formula to explain how gases are uniform when expanding; in other studies he defined the absolute boiling point of a substance. His studies of teases at high and low pressures moreover, allowed him to develop an accurate barometer and while working for the Russian navy, he came up with pyrocollodion, a smokeless powder based on nitrocellulose. The list of his achievements is endless!

Despite his international reputation as one of the world's most important scientists, the Tsar at the time did not approve of Mendeleev's politics, resulting in his resignation from the University of St Petersburg in 1900. He died on 20th January, 1907, from pneumonia.

Read the text and answer the questions in your own words.

1. What position did Mendeleev achieve at the University of St Petersburg?

2. Why did Mendeleev leave gaps in the periodic table of elements?

3. How were Mendeleev's predictions proven correct?

4. What contribution did Mendeleev make in the area of solutions?

5. What did Mendeleev's formula concerning gases explain?

 

Dmitri Mendeleev

1. Дмитрий Иванович Менделеев родился в 1834 году в большой семье - у его родителей было 14 детей.

2. В 1863 году Менделеев был назначен профессором химии в Технологическом институте и Университете Санкт-Петербурга.

3. Величайшим результатом его трудов стало открытие Периодического закона: Менделеев даже смог предсказать существование элементов, которые в его время ещё не были известны.

4. Менделеев занимался исследованиями во многих научных областях, включая гидродинамику, агрохимию, метеорологию и химическую технологию.

5. Менделеев открыл «температуру абсолютного кипения жидкостей», или критическую температуру.

6. Много времени он посвятил изучению растворов, значительно расширив наши знания в этой области.

7. Его работы с газами, находящимися под высоким или низким давлением, привели его к созданию точного барометра.

 


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