Learn the word definitions.

Vacant, adj. — 1. empty, not occupied by anyone: a vacant room e.g. in a hotel

— 1. 2. looking as if you do not understand or are not paying attention: a vacant expression/look/smile

Confidence, n — 1. expecting smth to be kept in secret or faith

2. secret e.g. to exchange secrets

3. the belief that someone or something is good and that you can trust them: e.g.to have/lose, restore confidence in.

Arrange, vt, vi — 1. put in order e.g. to arrange flowers; make plans in advance e.g. to arrange to meet smb

2. came to an agreement

3. adapt (a piece of music)

II. Reading

Read the text and write down all key words.

D.I. MENDELEYEV

Dmitry Mendeleyev was a Russian chemist and an inventor. He was also the father of Peri­odic Table of Elements. Mendeleyev was born on February 8, 1834 in Verkhnie Aremzyani vil­lage, near Tobolsk (Russia). At the age of four­teen, after the death of his father, Mendeleyev attended Tobolsk Gymnasium.

He enrolled (1850) in the Faculty of Phys­ics and Mathematics of the Main Pedagogical Institute in Saint Petersburg, from which he graduated with a brilliant record in 1855. He taught (1855—56) at the Odessa lyceum, where he continued work on the relationships between the crystal forms and the chemical composition of substances.

Between 1859 and 1861 he worked on the density of gases in Paris, and the workings of the spectroscope with Gustav Robert Kirchhoff in Heidelberg. In 1860, Mendeleyev discovered the concept of critical temperature and attended the first International Chemical Congress at Karlsruhe, where Stanis-lao Cannizzaro's views on atomic weights planted the seeds for the concept of the periodic table.

In 1863, after returning to Russia, he became Professor of Chemistry at the Saint Petersburg Technological Institute (1864—66) and at the University of Saint Petersburg (1867—90), where he gave a course of lectures in theoretical and prac­tical importance. Because he found no suitable text for his students, he wrote his own — Principles of Chemistry (1868—71).

The systematization of ideas required for this book led Mendeleyev to for­mulate the periodic law in March 1869. The law organized the chemical elements known at the time according to their atomic weights and predicted the existence of more elements.

He was sent (1876) by the Russian government to study petroleum produc­tion in the United States. Mendeleyev also worked on the liquefaction of gases; the expansion of liquids; a theory of solutions; a theory of the inorganic origin of petroleum; the chemistry of coal; Russian weights and measures; and the universal ether. He helped to found the Russian Chemical Society in 1868.

Though Mendeleyev was widely honored by scientific organizations all over Europe including the Copley Medal from the Royal Society of London. In his later years, he worked out and investigated the composition and fields of oil and helped to found the first oil refinery in Russia. He died in St. Petersburg (1907), Russia from influenza. His name will be perpetuated in the discovery of new artificial ele­ments and in our better understanding of the mysteries of nature. Element number 101, the radioactive mendelevium, is named after him.

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