2018-02-13
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4. Translate the following sentences into English:
1. Як мені відомо, азот і фосфор є найважливішими елементами в групі VI.
2. У лекції зазначалося, що за нормальних умов азот є газом, що складається з двоатомних молекул.
3. Відомо, що азот складає приблизно 60 відсотків усього об’єму атмосфери.
4. Ніхто не знає, що процес перетворення атмосферного азоту в формулу, яку утворюють рослини й тварини, називається фіксацією азоту.
5. Хочу додати, що цей процес є складовою частиною кругообігу азоту в природі.
6. Я десь читав, що щорічно у світі виробляють більше 100 млн. тон азоту.
7. Чи правда, що фосфор є найнеобхіднішим для життя елементом та входить до складу майже всіх організмів?
8. На мою думку, фосфор необхідний для побудови кісткової тканини та забезпечення організму енергією в процесі дихання.
9. Червоний фосфор використовують для виготовлення сірників, чи не так?
10. Варто зазначити, що фосфор входить до складу всіх мінералів, найважливішим із яких є апатит.
5. Translate the following text into English:
Ртуть відома зі стародавніх часів. Ртуть згадується у працях Аристотеля, Теофраста, Плінія Старшого, Вітрувія та інших давніх учених. Латинська назва цього металу “гідраргірум” означає в перекладі “срібна вода”. У величезному палаці знаменитого (famous for) своєю жорстокістю (cruelty) китайського імператора Цінь-Шіхуанді були створені цілі ріки й озера, наповнені (filled with) чистою ртуттю. За легендою, по цих небезпечних для дихання (breathing) річках імператор пропливав із наложницями на прикрашених човнах.
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Ртуть широко застосовується при виготовленні різних приладів (барометри, термометри, манометри тошо). Крім того, сполуки ртуті застосовуються в медицині.
Пари ртуті та її сполуки дуже отруйні (poisonous). З попаданням до організму людини через органи дихання, ртуть акумулюється та залишається там на все життя. Симптоми гострого отруєння проявляються через 8-24 години: починається загальна слабкість, головний біль та підвищується температура; згодом – болі в животі, розлад шлунку. Хронічне отруєння є наслідком вдихання малих концентрацій парів ртуті протягом тривалого часу. Ознаками такого отруєння є: зниження працездатності, швидка стомлюваність, послаблення пам'яті й головний біль.
TEXT 16
THE AGE OF POLYMER
Learn the new vocabulary:
| shelter | прихисток, житло |
| to supply | постачати |
| fur | хутро |
| leather | шкіра |
| resin | смола, каніфоль |
| rubber | резина, каучук |
| fragility | крихкість, слабкість |
| to defy | відмовлятися, не піддаватися |
| fibre (fiber) | волокно |
| coating | покриття, обшивка, шпаклівка |
| adhesive | клей. замазка |
| to repair | ремонтувати, лагодити |
| to be resistant to corrosion | протистояти іржі, окисленню |
| moisture | волога |
| durability | міцність, тривалість |
| to compete (with) | конкурувати, змагатися (з) |
| precipitate | осад |
| feeble efforts | незначні / слабкі спроби |
| intricacy | складність |
1. Read and translate the text:
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Life depends fundamentally on organic polymers. If it were not so, we wouldn't have food, clothing, shelter and transportation.
Indeed, nearly all of the material needs of man could be supplied by natural organic products. The list of these materials and things made of them might be very long: wood, fur, leather, wool, cotton, silk, rubber, oils, paper, paint and so on. The organic polymers which these things are made from include: proteins, cellulose, starch, resins, and a few other classes of compounds.
But for the complexity and fragility of the molecules of the natural organic polymers they wouldn't have defied the attempts to analyze their molecular structure until very recently.
There would be no industry of man-made organic polymers, were it not for modern methods of physical and chemical analyses which uncovered the principles that govern the properties of the natural polymers. One could list the principal products such as fibers, synthetic rubbers, coatings, adhesives and a lot of materials called "plastics". Plastics and synthetic coating are already in common use. It is desirable that they should be used on a large scale, and get further developed.
Synthetic polymers now available already possess several of the properties required in a structural material. They are light in weight, easily transported, easily repaired, highly resistant to corrosion and solvents, and satisfactorily resistant to moisture. It would be necessary to add that they have long-lived durability and resistance to high temperatures. A very important question could arise over whether synthetic polymers could be made inexpensive enough to compete with the structural materials such as metals and ceramics. The answer could be —"yes".
It might seem odd that man came rather late to the investigation of organic polymers as the principal means of supporting life. The natural polymers such as proteins, cellulose and others dominated his existence and even in ancient times people used these materials.
Yet as late as the end of the 19th century polymer chemistry got little attention.
Chemists attacked sugar, glycerol, fatty acids and other ordinary organic compounds — dissolving, precipitating, crystallizing and distilling them to learn what these substances were composed of.
But only feeble efforts were made to investigate such common materials as wood, starch, wool, and silk. The substances composing these materials couldn't be crystallized from solutions, nor could they be isolated by distillation.
It was only in the 20th century that the scientists began thorough investigation of these materials. Having used some powerful physical instruments, an electron microscope, viscosimeter, X-ray diffraction apparatus, they could have revealed the polymers in all their intricacy. Their molecules were incredibly large, the molecular weights running as high as millions of units, whereas simple organic substances such as, for instance, sugar and gasoline have molecular weights in the range of only about 50-500.
Giant molecules can be composed of a large number of repeating units, they being given the name "polymer" from the Greek word poly (many) and meros (a part). Many polymers have the form of long, flexible chains. If the chemists had not found that out, they wouldn't have been able to synthesize artificial polymers. This has led to the establishment of industries producing synthetic fibers and numerous polymeric materials, many of which were less expensive and superior in various ways to the natural materials.
2. Put the numbers of the given plan in the order of events they occur in the text:
1. The history of polymers.
2. Natural organic products.
3. The molecules of polymers.
4. Discoveries made by modern methods.
5. The importance of organic polymers.
6. New industries of man-made organic polymers.
7. Properties of synthetic polymers.
3. Answer the following questions:
1. What does thelife depend on?
2. Why does life depend upon organic compounds?
3. What is the list of materials needed for life?
4. What do organic polymers include?
5. What have modern methods of physical and chemical analyses uncovered?
6. What products appeared on the basis of the discovery of polymers?
7. What properties do synthetic polymers possess?
8. Did people use natural polymers in ancient times?
9. What were those polymers?
10. What is the origin of the word “polymer”?
11. Give examples of the polymers we eat.
4. Give chemical terms to the following definitions:
1. Any of large group of organic compounds found in all living organisms.
2. A synthetic or naturally occurring polymer used in making plastics.
3. A polysaccharide that consists of a long unbranched chain of glucose units.
4. A liquid that dissolves another substance or substances to form a solution.
5. A process of boiling a liquid and condensing and collecting a vapor.
6. A suspension of small particles produced in a liquid by chemical reaction.
7. A homogeneous mixture of a liquid with a gas or solid.
5. Translate the following sentences into Ukrainian:
1. It is necessary that this substance should be analyzed under suitable conditions.
2. If they used these materials, the cost of production would not be expensive.
3. Everybody should know that our scientists developed methods of obtaining strong and cheap glass fiber.
4. If you use such fibers, the material will be durable.
5. Had they known about this new discovery earlier, they would have applied the method in their investigation.
6. Were I in your place, I should investigate the properties of these synthetic materials before using them.
7. The professor insisted that I (should) take part in the conference.
8. It is desirable that a chemist (should) know the structure of a polymer.
9. Unless synthetic polymers possessed such valuable properties, they would not be so important for industry.
TEXT 17
PLASTICS
Learn the new vocabulary:
| but for … | якби не … |
| thread | нитка |
| moulded objects | формові / ливарні предмети |
| ancestor | предок |
| disadvantage | недолік |
| flammability | загоряння |
| desired shape | бажана / необхідна форма |
| rigidity | твердість, жорсткість |
| binder | зв’язувальна речовина |
| abrasion | стирання, зношування |
| flour | борошно, клейстер |
| to cast | кидати |
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1. Read and translate the text:
But for plastics man wouldn't have had an endless variety of products such as threads, sheets, tubes, moulded objects, etc. It is known that plastics are organic substances which are made synthetically by polymerization.
The ancestor of synthetic plastics is celluloid. If the properties of celluloid had been perfect, it could have been the basis for a new industry. But celluloid has certain disadvantage — its flammability. More than that, it is necessary that the material of this kind be readily moulded, which was not the case with celluloid. Thus it was not until the discovery of bakelite in 1907 that the real foundation of the synthetic plastics industry was laid.
Plastics consisting of long-chain molecules, they can be softened by heat and moulded into a desired shape. It is known that these plastics are thermoplastic. Plastics having cross-linked polymeric chains are of much greater rigidity and cannot be softened. They are called thermosetting. It is essential that the terms thermoplastic and thermosetting be also applied to the resins from which plastics are made, the resin being the principal agent incorporated in plastics. It may be natural, like cellulose, but it is most generally synthetic. It is also known that the resin is a binder.
There are some other substances added to the plastics without which it would not be possible to synthesize these wonderful materials. Because it is necessary that plastics should enhance such properties as hardness, resistance to shock, or resistance to abrasion, filters are added; examples of filters are: asbestos, glass fibres, and wood flour. It is required that plasticizers be also included in the formulation. Hadn't antioxidants been added, chemical stability and long life of plastics wouldn't have been possible. It was suggested that catalysts should be added to assist the final cure (final formation of the product). Furthermore, if it were not for stabilizers, plastics would not be protected against sunlight, heat and other destructive factors.
The procedure which is used to shape plastics into a final form depends on their properties. Some plastics may be injection moulded. Other plastics must be compression moulded. It means that after they are filled into the mould they must be subjected to pressure. Certain plastics are simply cast into their final shape.
2. Divide the text into logical parts, entitle them.
