English for chemists

Section П
Упр. 1. Прочтите заглавие текста 8 В. О чем, по вашему мнению, будет идти речь в этом тексте?
Упр. 2. Назовите значения следующих интернациональных слов:
metal, sclcnidc, proportion, material, action, chlorine, permanganate, cadmium, cobalt, nickel, zinc, product, process, contain
Упр. 3. Определите значения выделенных слов по контексту. Сино­ нимы в скобках помогут вам.
1. The atomic weight of selenium is approximately (about) 79.2. Whe H2SO4 is to be diluted with water, it must be poured into an excess (greater amount) of water. 3. Some reactions with conccntratcd sulphuric acid proceed quickly when they arc heated. 4. When sclcnious acid is treated with (actcd upon by) chlorine, selenic acid is produced. 5. When hydrogen sclcnidc forms, it bubbles (passes) into the liquids in the various bottles (containers for liquids). 6. The symbols Pb, Си, K, As and Sb stand for lead, copper,potassium, arsenic and antimony. 8. We obtained the product somewhat (to some extent) heavier than in the previous reaction.
Слова к тексту:
grind — измельчать; powder — порошок; mortar — ступа; dust — пыль; dry — сухой; vigorously — бурно; remove — удалять; lump — ку­ сок; transfer — перемещать; flask — колба; connect — соединять; flue — газоход

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Text 8 В
Прочтите текст про себя (контрольное время чтения — 5 минут).
Selenium Compounds
The element (selenium) can combine with the metals, just as sulphur can, forming sclenidcs. Let us grind some selenium to powder in a mortar. After that, wc should take 10 grams of this powder and grind it with 7 grams of iron dust, a proportion of 80 and 56, the approximate atomic weight ratio of the two elements. Then, wc must pour the well-mixed material into a dry test-tube and heat it. Ferrous scicnidc is formed, the action proceeds somewhat less vigorously than that between iron and sulphur. When the tube has cooled somewhat, wc can break it open and remove a grey-black product which much resembles ferrous sulphide. Selenium will unite similarly with zinc and with other metals such as coppcr and lead.
Selenium dioxide may be formed by the combustion of the element. The dioxide is white and can dissolve readily in water to form selenious acid just as sulphur dioxide dissolves to form sulphurous acid:
HjO + ScO; —>H’ScOj.
When selenious acid is treated with chlorine or potassium perman­ ganate, sclenic acid is produced; the proccss, of course, can be callcd oxidation, the reaction proceeds just as it does with sulphurous acid. Small lumps of ferrous selenidc arc transferred to a small flask connected to a train of bottles containing solutions of a number of different metallic salts, for example, those of cadmium, cobalt, nickel, arsenic, and antimony. Any excess of gas which may escape is led into the flue. Add some hydrochloric or sulphuric acid to the material in the flask, and presently hydrogen selenidc forms and bubbles into the liquids in the various bottles. Various selcnidcs can be formed.
Упр. 4. Действительно ли текст 8 В содержит ту информации», кото­ рую вы ожидали в нем найти? Скажите, что было для вас новым.
Упр. 5. Разделите текст на тематические части и озаглавьте каж­ дую часть.
Упр. б. Скажите, что говорится в тексте:
1) о способности селена реагировать с металлами; 2) о реакции се­ лена с железом; 3) об образовании диоксида селена; 4) об образовании селенистой кислоты; 5) о получении селеновой кислоты.
Упр. 7. Найдите в тексте отрывок, гае описывается получение селс-нида водорода; переведите его на русский язык.

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Scction III
Ex. 1. Think of the situations when the following expressions may be used: be going to\ be worth (white) + существительное или герундий; be used to
Examples: l . I ’m going to finish this work at home.
2.Thc book is w orth reading, but it is difficult to get it. 3.Нс is used to doing everything quickly.
Ex. 2. Translate the scntenccs into English, using expressions from exercise 1.

1. 
   Я не собираюсь делать домашнее задание сегодня. Уже поздно.
   

2. 
   Я не буду заниматься иностранным языком регулярно. 3. Она при­ выкла вставать рано. 4. Есть студенты, которые привыкли получать хорошие оценки. 5. Он начнет реакцию заново, реагент был недоста­ точно чистый, б. Она говорила, что собирается на этот фильм. 7. Мы не привыкли переводить текст без словаря. 8. Стоит научиться пи­ сать сразу без ошибок, не придется тратить время на переписывание.
   

9. 
   Он не привык к таким запахам. 10. Свойства некоторых соедине­ ний стоит запоминать. 11. Сейчас эту статью читать не стоит, она
   

будет для вас трудна.
Ex. 3. Make up sentences or short stories with the following words:

1. 
   clement, importance, abundant, little, commercial, selenium, be;
   

2. 
   selenium, alike, property, atomic sulphur, be, weight, greater; 3) can, several, form, selenium, find, allotropic; 4) odourless, selenium, be, both...
   

and..., tasteless, in colour, or, hard, red, dark, may; 5) metal, selenium, combine, form, can, selcnidcs

Ex. 4. Give detailed answers to the following questions:
1. What are the physical properties of selenium? 2. What do you know about chemical properties of selenium? 3. In what respect are selenium and sulphur alike? Why? 4. What selenium compounds do you know? 5. What methods of the preparation of selcnidcs do you know?
Ex. 5. Discuss the following topics:

1. 
   An Abundance of Selenium and Its Compounds.
   

2. 
   The Similarity of the Properties of the Elements Occurring in Group VI.
   
3. 
   The Description of the Properties of Selenium.
   
4. 
   Selenium Compounds.
   

DO YOU KNOW THAT...

In 1817 Berzelius managed to obtain a brown-red powder. It burned like sulphur. He established that it was a new element. He remembered the

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other element with the similar properties — tellurium which has been given its name in the honour of die earth (from Greek “tcllus” meaning “earth”). He decided to name the newly-discovered element in honour of the moon, that is why it is callcd selenium.