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Chemistry

Biology | Vocabulary | Pedology | Signs of Life | At the Cradle of Life | Melvin Calvin | Photosynthesis | Antoine-Laurent Lavoisier | Geosciences | Vocabulary |


Chemistry is the science concerned with the composition and properties of matter, changes, the conditions under which such changes take place and the alterations in energy levels which accompany them. A chemical change is a change that takes place in a substance, during which it breaks up into simpler substances or it combines with different properties or characteristics.

Chemistry is concerned with the nature of fire and the structure of water. It deals with colours, catalysis and crystal structure, with physical properties and chemical reactivity. Chemistry is one of the fundamental sciences. It plays an important part in the development of biochemistry, physics, geology and many other fields of science.

Chemistry has two main aspects: descriptive chemistry (the discovery of chemical facts) and theoretical chemistry (the formation of theories).

The broad field of chemistry may be divided into two branches: organic chemistry and inorganic chemistry. Organic chemistry deals with the compounds of carbon that occur in plants and animals. Inorganic chemistry is concerned with the compounds of elements other than carbon. Each of these branches of chemistry has in part practical and theoretical applications.

Chemistry's origin goes back to ancient times with the manufacturing of bronze, iron, ceramics and glass. At the end of the 16th century newly discovered natural laws, entirely free of magic which surrounded the work of the alchemists, appeared. In the 17th century modern chemistry began with the work of Robert Boyle. He was the first to study the relationship between the volume of a gas and the external pressure upon it. Later A. Lavoisier introduced the concept of chemical elements. In the 19th century A. Avogadro suggested that matter can be studied in units called molecules. He stated that equal volumes of gases under the same conditions of temperature and pressure contain the same number of molecules. F.A. Kekule and A.B. Butlerov introduced the structural theory of organic Chemistry.

In 1869 D.I. Mendeleyev made the greatest discovery in the sphere of chemistry. He observed certain patterns and regularities in the composition of matter and from this created the first elemental chart. The achievements in chemistry 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. In the last few decades 11 new radioactive elements were obtained. Two of them were named in honour of Russian scientists: the 101st was called Mendelevium and the 104th - Kurchatovium (in memory of Igor Kurchatov).

Many great scientists devoted their lives to the development of chemistry. They were: Bohr, whose theory of the hydrogen atom was very important; the Curies, who in 1934 announced the preparation of radio-active elements; Marie Curie who alone discovered radium and the element polonium.

Russian chemists also made great contributions to the world of science. Among them were the outstanding Russian chemists M.V. Lomonosov, D.I. Mendeleyev, A.M. Butlerov, N.N. Semenov, N.D. Zelinsky and many others.

Academician N.N. Semenov has made great discoveries in the field of chain reactions. He has formulated the theory of chemical chains and branched reactions. N.D. Zelinsky's works have formed the basis for the synthesis of a large number of new compounds. A team of researchers has evolved a new method of extracting phenol and aceton from benzene and propylene.

Chemistry is so much a part of our lives that it is very easily taken for granted. Metals, glasses, plastics, dyes, insecticides, paints, paper, soap and perfumes are all made of chemicals.

The Faculty of Chemistry at Rostov State University has six departments: the Department of General and Inorganic Chemistry, the Department of Analytical Chemistry, the Department of Organic Chemistry, the Department of Physical and Colloid Chemistry, the Department of Electrochemistry and the Department of Chemistry of Nature and Higher Molecular Compounds.

Students also major in solid state chemistry, environmental control, chemical strength of materials and food inspections.

Graduates of this faculty can do research in the fields of analysis and synthesis of organic compounds, oxidation and environmental protection. They are certified as professional chemists, pharmacists and are qualified to teach chemistry.

(Adapted from the Internet sites)

 

3.2 What new information about chemistry have you learnt from the text you have read?

 


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