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Read the text dealing with discovery of metals and opening the Periodic Law




Metals in Periodic Table

Chemical elements were being studied for a long time in the middle of thе 18th century. French scientist Lavoisier laid the foundation of the chemical science, having started the quantitative analysis of the elements. Early in the 19th century English chemist John Dalton tried to establish the atomic theory. By the middle of the 19th century chemical elements had been classified into two general groups: metals and non-metals.

The step forward during this period was the idea of new concept called “valence”, which meant the capacity of atoms to combine with one another. Later, it was found that the properties of chemical elements depend on their atomic weight. So, a Russian scientist D. I. Mendeleyev (1834–1907) could build up a periodic classification of all the then known elements. According to his theory, Mendeleyev predicted the properties of some undiscovered elements for which he left blank spaces. The theory became true and in 1875 such elements as gallium was discovered, taking the place below zinc. Scandium was discovered in 1879, filling the gap below calcium and germanium – in 1886, taking the place near gallium, below zinc. In the memory of the originator of the Periodic Law the 101st element discovered by American scientists in 1951 was named mendeleyevum. Mendeleyev’s Periodic law is regarded to be one of the most recognized and important achievements in science.

D. I. Mendeleyev was not the only Russian scientist dealing with metals. M. V. Lomonosov formulated the first definition of the word “metal” in the following way: “A metal is a bright solid that can be forged”. Besides, the characteristic features of metals are lustre, toughness, workability, electrical and heat conductivity and others. Metals are well processed materials. They can be cast, forged, stamped, extruded, rolled, cut, welded.

It is the presence of iron that divides metals into ferrous and non-ferrous. And it is by this reason that iron may be considered to be the most important element in Periodic Table. The abundance in which iron is founded, its great strength, its remarkable ductility and malleability make it especially suitable for many works where strength with lightness are required. However, in ancient states the use of iron, either cast or wrought, was rather limited, bronze being the favourite metal almost for all purposes. Bronze is known to be the alloy of copper and tin.

Bronze and other non–ferrous metals, such as gold and silver, may be treated in various ways, the chief of which are: casting in mould and treatment by hammering and punching. Along with bronze brass (an alloy of copper and zinc) is widely used because of its cheapness in comparison with bronze. Besides, analyses of the iron of prehistoric weapons showed that they contained a considerable percentage of nickel. And in many specimens of ancient bronze, small quantities of silver, lead and zinc were also found.

It is worth mentioning that both ferrous and non-ferrous metals are widely used in a great variety of works and non-ferrous materials are predominant in works of art. Many metals of Periodic Table can interact with each other and develop quite new materials and alloys. For example, aluminium oxide which is also referred to as corundum, sapphire, ruby or aloxite are mentioned in the mining, ceramic and materials science. Rubies are given their characteristic deep red colour and laser qualities by adding such metallic element as chromium. Sapphires come in different colours given by impurities of iron and titanium. Aluminium oxide is widely used in the fa­brication of superconducting devices, particularly single electron transistors and superconducting quantum interference devices (SQUID).

Such metals as boron and nitrogen form boron nitride known as Borazon. The latter is a crystal created by heating equal quantities of boron and nitrogen at temperatures greater than 18000C (3300 F) at 7 GPa (1 million lbf/in2). Borazon replaced aluminium oxide for grinding hardened steels due to its far superior abrasive properties. Other uses include jewellery designing, glass cutting and laceration of diamonds.

 

17.Complete the sentences:

1. Chemist who established the atomic theory was…

2. There are two general groups of metals:…

3. The capacity of atoms to combine with one another is called…

4. For undiscovered elements Mendeleyev left…

5. The 101st element was named in the memory of …

6. The most important element in Periodic Table is…

7. In ancient works of art the most widely spread metal (alloy) was…

8. Aluminium oxide is widely used in …

9. Borazon replaced aluminium oxide due to …

 

18.Insert the proper words into the sentences:

1. Chemists found a new (поняття) called (валентність).

2. (Властивості) of chemical elements (залежать від) their (ваги атомів).

3. According to Mendeleyev’s theory it is possible (передбачити) the properties of elements.

4. Lomonosov gave the first (визначення) of metal.

5. Iron owing to its (еластичність) and (ковкість) is widely used metal.

6. Bronze is (сплав) of copper and tin.

7. In many (зразків) of ancient bronze some (домішок) of other metals have been found.

8. (Кольорові метали) are mainly used in works of art.

19.Find in the text the sentences that correspond to the following statements:

1. In the middle of 19th century classification of chemical elements appeared.

2. Due to the quantitative analysis of chemical elements new concept emerged.

3. Mendeleyev’s theory gave the opportunity to foresee the properties of elements.

4. Gradually several elements which filled the gaps in the Table were discovered.

5. Metals can be processed by various operations.

6. Owing to its qualities iron is the most important element in the Table.

7. Earlier the most popular metal was bronze.

8. Ancient weapons contained impurities of several non-ferrous metals.

9. Interaction of metals can result in other materials and alloys.

10. Such metal as boron possesses high strength and is used for grinding hardened steels and cutting diamonds.

VOCABULARY

1. copper   мідь
2. bronze   бронза
3. steel   сталь
4. brass   латунь
5. pewter   олово
6. zinc   цинк
7. invar   інвар
8. solder   припій
9. carbon   вуглець
10. cast iron   чавун
11. alloy   сплав
12. property   властивість
13. application   застосування
14. non-ferrous   кольорові метали
15. to extract   видобувати
16. pure copper   чиста мідь
17. ductile   пластичний
18. domestic appliances   предмети домашнього вжитку
19. conductor   провідник
20. corrosion resistant   корозієстійкий

Література

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2. Бонами Д. Английский язык для будущих инженеров: Учеб. пособие / Дэвид Бонами / Предисл. В.Б. Григорова; Пер. «Методических указаний» и словарей Л.И. Кравцовой. – 2-е изд., - М.: Высш. Шк., 1994. – 287 с.: ил.

3. Воскресенская, Л.И. Металлы и металлорежущие станки / Metals And Metal-Cutting Machine-Tools: учеб. пособие по английскому языку / Л.И. Воскресенская, И.А. Рожнова. – Омск: Изд-во ОмГТУ, 2009. – 60 c.

4. Иванов С.С. Английский язык для студентов технических вузов: учебное пособие. под ред. С.С. Иванова. / С.С. Иванов, Е.В. Волкова, Е.Н. Лебедева и. др. – Нижний Новгород: НГТУ, 2006. – 101 с.

5. Мантатова С.С. Engineering MOSAIC: English for science and technology: Учебное пособие для студентов технических для студентов технических специальностей вузов и колледжей / С.С. Мантатова, Э.Т. Левчук, Г.Б. Доржиева – Улан – Уде: изд-во ВСГТУ, 2007. – 82 с.: ил.

6. Орловская И.В. Учебник английского языка для студентов технических университетов и вузов. – 6-е изд. / И.В.Орловская, Л.С. Самсонова, А.И. Скубриева – М.: Изд-во МГТУ им. Н.Э. Баумана, 2006. – 448 с.

7. Bingham C. Technical English 2. Teacher’s Book / Ceila Bingham. – Pearson Education Limited. Longman, 2008. – 141 p.

8. Bonamy D. Technical English 2. Course Book / David Bonamy. – Pearson Education Limited. Longman, 2008. – 127 p.

9. Comfort, J. Basic Technical English. / Jeremy Comfort, Steve Hick, Allan Savage. – Oxford University Press, 2006. – 44 p.

10. Glendinning H.E. Oxford English for Careers. Technology 1. / Eric H. Glendinning. – Oxford University Press. 2006, 135 p. – www.oup.com/elt.

11. Glendinning H.E. Oxford English for Careers. Technology 2. / Eric H. Glendinning, Alison Pohl. – Oxford University Press, 2006, 135 p. – www.oup.com/elt.

12. Harding K. English for Specific Purposes / Keith Harding. – Oxford University Press, 2007. – 170 p.

13. Hollet V. Tech Talk. Elementary Student’s Book / Vicki Hollet. – Oxford University Press, 2003. – 128 p.

14. Jacques Ch. Technical English 2. Workbook / Christopher Jacques. – Pearson Education Limited. Longman, 2008. – 80 p.

15. Змістова частина галузевих стандартів вищої освіти підготовки фахівців освітньо-кваліфікаційних рівнів молодшого спеціаліста та бакалавра щодо гуманітарної освіти / Інформаційний вісник. Вища Освіта. - №11, 2003. – К., 2003 – 60с.

16. Longman Dictionary of Contemporary English. / [director, Della Summers]. – New ed. – Pearson Education Limited. – 2003. – 1950 p.

17. The Oxford Encyclopedic English Dictionary / ed. by Pearsal J., Trumble B. – New York: Oxford University Press, 1996 – 1766 p.

Tech Talk Teacher's Site – http://www.oup.com/eltnew/catalogue/teachersites/techtalk/?cc=ru

 





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