Химия D. I. MENDELEYEV просмотров - 221
Some facts about chemistry
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The science of chemistry deals with substances. Chemistry is the investigation and discussion of the properties of substances.
Common examples of substances are: water, sugar, salt, copper, iron and many others. Chemists study substances in order to learn as much as they can about their properties and about their reactions that change them into other substances. This knowledge is very important as it can make the world a better place to live in, it can make people happier, and it can raise their standard of living.
Chemist discovered many laws, investigated many important phenomena in life. They produced many artificial substances which have valuable properties. Chemistry has two main aspects: descriptive chemistry, the discovery of chemical facts, and theoretical chemistry, the formulation of theories.
The broad field of chemistry may also be divided in other ways. An important division of chemistry is that into the branches of organic chemistry and inorganic chemistry. Organic chemistry is the chemistry of the compounds of carbon that occur in plants and animals. Inorganic chemistry is the chemistry of the compounds of elements other than carbon. Each of these branches of chemistry is in a part descriptive and in part theoretical.
Chemistry plays an important role in the development of other sciences such as physics, biochemistry, geology and a lot of others sciences. The famous chemists are: N. Kurnakov, N. Zelinsky, A. Favorsky, A. Arbuzov, A. Butlerov, N. Semenov.
D.I. Mendeleyev, the great Russian chemists, was born in Siberia in February 8, 1834. When he was seven years old he went to gymnasium at Tobolsk. He studied very hard; he especially liked mathematics, physics and history. At the age of 16 he entered the Pedagogical institute in St. Petersburg, physic-mathematical department. He graduated from the institute in 1855 and began to teach chemistry at the Technological Institute and then at the University. In 1865 he was granted the doctor of Science degree for thesis on the combination of alcohol with water. This work was both of great theoretical and practical significance. Soon after that Mendeleev was appointed Professor of General Chemistry of St. Petersburg University. Despite lectures and supervision of the laboratory he carried on great research work.
Mendeleev’s greatest discovery was the Periodic Law. The Periodic Law suggested by Mendeleev stated that the properties of the elements were periodic functions of their atomic masses. He presented this work to the Russian Chemical Society. Mendeleev’s Periodic Law opened a new era in the history of chemistry.
Mendeleev was interested in many branches of science, indeed there is hardly any field of science that was not enriched by his contribution. His numerous works dealt with many subjects; properties of liquids, theories of solutions, the development of the gas law and many others.
D.I. Mendeleev was a great patriot. He did everything for the development and progress of his country. He continued his research work to the very last day of his life. He died in 1907.
The world is thankful to Mendeleev for his great contribution to the world science. At present there is hardly anybody who doesn’t know this Russian scientist and his Periodic Law.