Указания к выполнению контрольных заданий 


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Указания к выполнению контрольных заданий



Указания к выполнению контрольных заданий

Каждое контрольное задание в данном пособии предполагается в пяти вариантах.

Студент должен выбрать один из пяти вариантов в соответствии с последними цифрами студенческого шифра: студенты шифр которых оканчивается на 1 или 2 - вариант №1, на 3 или 4 - №2, на 5 или 6 - №3, на 7 или 8 - №4, на 9 или 0 - №5.

Каждому варианту соответствует своя цифра (1 вариант Unit 1, 6; 2 вариант Unit 2,7; 3вариант Unit3,8; 4 вариант Unit 4,9; 5 вариант Unit 5, 10)

1 контрольная – задание №1,2 из Unit 1-5 в соответствии со своим вариантом

2 контрольная – задание №1,2 из Unit 6-10 в соответствии со своим вариантом

3 контрольная – задание №3 из Unit 1-5 в соответствии со своим вариантом + письменное реферирование текста из упражнения №1

4 контрольная – задание №3 из Unit 6-10 в соответствии со своим вариантом + письменное реферирование текста из упражнения №1

 


Unit 1

 

I. Прочитайте и переведите текст.

 

Chemistry

Chemistry is the science which deals with materials, their properties and the transformations they undergo. So chemistry is the study of composition and properties of matter, their changes, the conditions under which such changes take place, and the energy changes which accompany them.

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’s origin goes back to ancient times, with the manufacture of bronze, iron, ceramics, glass.

In the 17th century modern chemistry began with the work of Robert Boyle. He was the first one who studied quantitatively the relationship between the volume of a gas and the external pressure upon it. Later A. Lavoisier introduced the concept of the chemical elements.

Many great scientists devoted their life to the development of chemistry, among them Bohr whose theory of the hydrogen atom was very important, the Curies who in 1934 announced the preparation of artificially radio-active elements, Marie Curie who discovered radium and the element polonium.

Many great Russian chemists made a great contribution to the world science. Among them, the outstanding Russian chemists M. V. Lomonosov, D. I. Mendeleyev, A. M. Butlerov, Academician N. N. Semenov, and many others.

Everyone now understands the importance of chemistry. The future of chemistry is practically unlimited. Rapid development of chemical industry will make it possible create many new goods, machines, plastics, polymers, it will help to understand many new phenomena.

1. Chemistry is the study of substances, their structure, their properties and their reactions.

2. Matter exists as solids, liquids, or gases.

3. Homogenous material is material with the same properties throughout.

4. Heterogeneous material is material consisting of the parts with different properties.

5. Compound is a substance that can be decomposed into two or more substances.

6. Substance is a homogenous species of matter with definite chemical composition.

7. Chemical reactions are the processes that convert substances into other substances.

8. Alloy is a metallic material containing two or more elements.

 

Vocabulary

  1. to deal with – иметь дело, рассматривать, касаться
  2. to take place – иметь место, происходить
  3. to be concerned with – иметь дело с
  4. to devote to – посвящать
  5. to make a contribution to – делать вклад
  6. to accompany – сопровождать
  7. relationship – связь, отношение
  8. property – свойство
  9. to announce – объявлять, заявлять
  10. rapid – быстрый
  11. species – вид
  12. to convert – преобразовывать
  13. alloy – сплав
  14. to contain – содержать, вмещать
  15. substance – вещество
  16. to undergo – подвергаться
  17. composition – состав
  18. compound – содержание
  19. matter – вещество
  20. to create – издавать

 

II. Выполните упражнение

1. Ответьте на вопросы к тексту

1. What do you know about chemistry? 2. What does chemistry study? 3. What does chemistry deal with? 4. Why is chemistry one of the fundamental sciences? 5. When did sufficient facts about chemistry appear? 6. When did modern chemistry begin? 7. Who was the first to study quantitatively the relationship between the volume of a gas and the external pressure upon it? 8. What did Lavoisier introduce? 9. Who discovered regularities in the properties of the elements? 10. What can you tell about the future of chemistry?

2. Найдите пары антонимов:

internal, to appear, natural, old, to disappear, artificial, new, external;

Найдите пары синонимов:

to deal with, to change, to start, field, to be concerned with, to alter, branch, to begin.

Переведите слова в скобках на английский язык

1. Chemistry is a science which (рассматривает) with materials and their properties. 2. We think that the exhibition of our achievements (состоится) at the end of September. 3. This scientist (внес большой вклад) both in chemistry and physics. 4. All his life he worked in the field of chemistry, and we can say that he (посвятил) his life to science. 5. All the changes which (сопровождали) this reaction play a very important role. 6. Later Lavoisier (ввел) the concept of the chemical elements. 7. Though these two teams work under (одинаковые) conditions the result of their work are different. 8. This article (касается) the development of our industry.

Определите видо-временную форму глагола и залог сказуемого и переведите предложения на русский язык

1) The properties of this substance change water heating.

2) The change from one state into another was accompanied by the evolution of the heat.

3) The concentration of mineral matter in sea water slowly increased.

4) Chemists discovered many laws and important phenomena in life.

5) The broad field of chemistry is divided in many ways.

6) Compounds of carbon occur in plants of animals.

7) The experiment were made under room temperature.

 

Сделайте письменный пересказ текста

 

III. Control text

Прочитайте и переведите текст. Выберите подходящее заглавие из ниже приведенных и обоснуйте свой выбор на английском языке.

 

1. The Scope of Chemistry.

2. The Nature of Chemistry.

3. The Body of Chemical Knowledge.

4. The Work of a Chemist.

5. Chemical Education.

 

What is chemistry? A popular dictionary gives this definition: Chem­istry is a science of the composition, structure, properties, and reac­tions of matter, especially of atomic and molecular systems. Another, somewhat simpler dictionary definition, is: Chemistry is a science dealing with the composition of matter and the changes in composi­tion that matter undergoes. Neither of these definitions is entirely ade­quate. Chemistry, along with the closely related science of physics, is a fundamental branch of knowledge. Chemistry is also closely related to biology not only because living organisms are made of material sub­stances but also because life itself is an essentially complicated system of interrelated chemical processes.

The scope of chemistry is extremely broad. It includes the whole universe and everything, animate and inanimate, in it. Chemistry is concerned not only with the composition of matter, but also with the energy and energy changes associated with matter. Through chemistry we seek to learn and to understand the general principles that govern the behavior of all matter.

The chemist, like other scientists, observes nature and attempts to understand its secrets: What makes a rose red? Why is sugar sweet? What is occurring when iron rusts? Why is carbon monoxide poison­ous? Why do people wither with age? Problems such as these — some of which have been solved, some of which are still to be solved — are part of what we call chemistry.

A chemist may interpret natural phenomena, devise experiments that will reveal the composition and structure of complex substances, study methods for improving natural processes, or, sometimes, synthe­size substances unknown in nature. Ultimately, the efforts of successful chemists advance the frontiers of knowledge and at the same time contribute to the well-being of humanity. Chemistry can help us to understand nature, however, it is not necessary to be a professional chemist or scientist to enjoy natural phenomena. Nature and its beau­ty, its simplicity within complexity, are for all to appreciate.

The body of chemical knowledge is so vast that no one can hope to master it all, even in a lifetime of study. However, many of basic con­cepts can be learned in a relatively short period of time. These basic concepts have become part of the education required for many profes­sionals including agriculturists, biologists, dental hygienists, dentists, medical technologists, microbiologists, nurses, nutritionists, pharma­cists, physicians, and veterinarians, to name just a few.

 

Test 1

1.People … chemistry since ancient times.

a) have practiced

b) are practicing

c) had practiced

d) practiced

 

 

2. Chemistry … the studies of the whole universe and everything in it.

a) is included

b) includes

c) include

d) included

 

3. Chemistry doesn’t study …

a) composition of substances

b) behavior with other materials

c) states of matter

d) human races

 

4. The history of chemistry …to ancient times.

a) goes back

b) concerns

c) deals with

d) considers

 

5. Chemistry … to other sciences e.g. physics and biology

a) is formed

b) is devoted

c) is related

d) is included

 

6. The building blocks of matter are …

a) atoms

b) elements

c) alloys

d) compounds

 

7. Different matters can be classified according do their …

a) masses

b) numbers

c) atoms

d) properties

 

8. One substance can be … into the other substance under chemical reaction.

a) formed

b) converted

c) included

d) introduced

 

9. The forms of … are solids, liquids and gases.

a) alloy

b) substance

c) matter

d) reaction

 

  1. Chemical reactions … by definite changes in energy

a) are accompanied

b) are changed

c) are made

d) are introduced

 

Unit 2

 

Vocabulary

1. rare – редкий

2. ability – способность

3. decay – разрушения

4. acid – кислота

5. to damage – делать вред

6. to contain – содержать

7. to urge – понуждать

8. to prolong – продлевать

9. raw materials – сырье

10. to separate – отделять

11. remedy – средство

12. steam – пар

13. efforts – усилия

14. attempts – попытки

15. to evolve – развиваться

16. to lead – руководить

17. essential – существенный

18. evidence – свидетельство

19. to improve – улучшать

20. to apply – применять

 

II. Выполните упражнения

 

1. Ответьте на вопросы.
1. What is alchemy? 2. What do you know about alchemists? 3. When did they experiment? 4. Why were their ideas forgotten? 5. Why did every medicine fighting ageing contain gold? 6. What made alchemy a formal discipline? 7. When and where did alchemy appear? 8. What did some physicians use to produce medicines in the Middle Ages? 9. Who was the first to unite alchemy with chemistry? 10. What laid the foundation for modern chemistry? 11. What was the idea of ancient scholars about the four essential ele­ments?

 

Сделайте аннотацию текста.

III. Control text

Прочитайте и переведите текст.

Modern chemistry was slower to develop than astronomy and physics. It began in the 17th and 18th centuries when Joseph Priestley (1733-1804), who discovered oxygen in 1774, and Robert Boyle (1627-1691) began to record and publish the results of their experi­ments and to discuss their theories openly. Boyle, who has been called the founder of modern chemistry, was one of the first to practice chemistry as a true science. He believed in the experimental method. In his most important book, The Sceptical Chemist, he clearly distin­guished between an element and a compound or mixture. Boyle is best known today for the gas law that bears his name. A French chemist, Antoine Lavoisier (1743—1794), placed the science on a firm founda­tion with experiments in which he used a chemical balance to make quantitative measurements of the weights of substances involved in chemical reactions. The use of the chemical balance by Lavoisier and others later in the 18th century was almost as revolutionary in chemis­try as the use of the telescope had been in astronomy. Thereafter, chemistry became a quantitative experimental science. Lavoisier also contributed greatly to the organization of chemical data, to chemical nomenclature, and to the establishment of the law of conservation of mass in chemical changes. During the period from 1803 to 1810, John Dalton (1766-1844), an English schoolteacher, advanced his atomic theory. This theory placed the atomistic concept of matter on a valid rational basis. It remains today as a tremendously important general concept of modern science. Since the time of Dalton, knowledge of chemistry has advanced in great strides, with the most rapid advance­ment occurring at the end of the 19th century and during the 20th century. Especially outstanding achievements have been made in de­termining the structure of atom, understanding the biochemical fundamentals of life, developing chemical technology, and mass produc­tion of chemicals and related products.

Озаглавьте текст. Разделите текст на логические части и выпишите из текста предложения, выражающие основную мысль каждой части.

Test 2

 

1. The principle goal of alchemist way to find a method of … human life.

a. prolonging

b. improving

c. ageing

d. treating

 

 

2. Alchemist ranted to change base metals into …

a. remedy

b. perfect metals

c. gold

d. some medicines

 

 

3. Modern chemistry began to develop from the world of …

a. Antoine Lavoisier

b. Joseph Priestley

c. John Dalton

d. Thadeus of Florence

 

 

4. Many years ago people … gold as a rare substance.

a. valued

b. had valued

c. have valued

d. were valueing

 

 

5. Alchemist tried to produced medicines from … materials.

a. base

b. new

c. different

d. raw

 

 

6. The study of alchemy … the birth of modern chemistry.

a. stopped

b. prevented

c. blocked

d. led

 

 

7. Outstanding achievements have been made … determining the structure of a tom.

a. from

b. of

c. out

d. in

 

 

8. The theory of Dalton placed the atomic concept of matter on a … basis.

a. valid

b. structural

c. essential

d. modern

 

9. Doctors … people to drink from gold cups

a. led

b. urged

c. insisted

d. tried

 

 

10. Earth, air, fire, water … up of a combination of basic.

a. made

b. make

c. have been made

d. are made

 

Unit 3

 

The Nature of Ceramics

One of the first solid materials, if not the very first, that man learned to use was ceramic natural stone. It was used in a variety of applications because of its characteristic properties such as hardness, strength to chemical attack which make it comparatively easy to shape. Thus natural ceramics provided man with tools, durable containers and even a roof. It is not surprising that man got greatly interested in ceramics and tried to create ceramics such as: pottery, bricks, concrete, glass. These products are spoken of as main industrial products to this day.

Ceramic material have been extended greatly. They range from dull clay to lustrous ruby, from the refractory linings to electronic control devices.

What is ceramics? Can this question be answered? Essentially it is defined as a combination of one or more definite metals with a non-metallic element, usually oxygen. The comparatively large oxygen atoms serve as a matrix with the small metal atoms. The main characteristic of the construction of ceramic crystals is that the atoms are linked by bonds that are primarily ionic but also to a significant extend covalent. These bonds are responsible for the stability and strength of ceramic materials. In the combination of oxygen atoms with metal atoms the ionic bonds are particularly strong. It should be noted that each oxygen atom with two electronic vacancies in its outer shell borrows two electrons from its metal neighbors, thus both kinds of atom become highly ionized – one negatively, the other positively.

As highly oxidized compounds the ceramics are strongly resistant to attack by nearly all chemicals. This accounts for many of their uses, even the making of steel depends on the use of ceramics.

A lot of analyses have been made by chemists. They found that the principal elements, for instance, in natural clays were oxygen, silicon and aluminium. They form the compounds known as aluminosilicates.

But a giant step forward in ceramic science came when crystal structures were analysed by means of X-ray diffraction. It has been found out that in the construction of ceramic materials much depends on how the atoms are stacked.

Many scientists both in Soviet Union and abroad work at the investigation of the properties of ceramic products. Many ceramic materials are being mass-produced now. They can be drawn into rods, cast or pressed. These ceramics are light in weight, but very strong. Some of tem are so hard that they can cut steel. You can hardly find any branch of industry where ceramic products are not used.

 

Vocabulary

  1. if not the very first – если не самый первый
  2. it should be noted – необходимо отметить
  3. to account for – объяснять
  4. mass-produced materials – изделия массового производства
  5. solid – твердый
  6. variety – разнообразие
  7. hardness - твердость
  8. to provide – обеспечивать
  9. durable - прочный
  10. pottery – гончарное изделие
  11. dull – тусклый
  12. bond – связь
  13. outer – внешний
  14. to cast – отливать
  15. to cut – резать
  16. oven – печь
  17. shell – оболочка
  18. to borrow – заимствовать
  19. device – прибор
  20. tо serve - служить

 

II. Выполните упражнения

 

1. Ответьте на вопросы.

1. What was the very first solid material that man began to use? 2. What did natural ceramics provide man with? 3. Why was ceramics used in a variety of applications? 4. Why did man get interested in ceramics so much? 5. What is ceramics? 6. What is a main characteristic of the construction of ceramics crystals? 7. Why are the ceramic materials so strongly resistant? 8. What are the principal elements in natural clays? 9. What does the construction of ceramic materials depend on? 10. Why are ceramic materials mass produced? 11. Why is the ceramic industry so important?

 

III. Control Text

Прочитайте и переведите текст.

 

An iron rod held in the fire long enough increases in energy content until it becomes too hot to hold in the unprotected hand. Nevertheless the rod is still iron, and when cooled to its original temperature, its properties are just as the were before.

The heating and the subsequent cooling of the rod are examples of physical changes.

A physical change may result in a more or less temporary alteration of a few of the properties of a substance involved, but no change of composition results from it and most of the altered properties usually regain their former value.

Changes of this type are numerous and many of them are familiar to everyone. As an example we may take the behavior of ice when its heated.

At first when heated the ice melts, when further heated, the liquid water boils forming the gaseous water (or the steam, as its usually called). If the steam is cooled, the process is reversed – when cooled sufficiently, the ice result. The substance present in every instance was water. This experiment shows that there are three physical states in which the substance may exist.

If the rod concerned is placed in a container of hydrochloric acid, it will be noted that bubbles begin to form on the rod. If the rod involved is left in the acid for some time, the evolution of gas will continue. When examined, it will be found that the rod has diminished in mass or disappeared altogether. The liquid in the container if examined will have a greenish colour.

If evaporated, a mass of greenish crystals will be obtained. The crystals will have totally different properties. This is an example of a chemical change. So, a chemical change may be called a chemical reaction or simply a reaction, the substances entering into a chemical reaction are called reactants.

Phenomena accompanied by radical changes of substances are called chemical phenomena.

 

Test 3

1. Pottery, brick and porcelain with glass provide the class of materials known as…

a) non-metals

b) ceramics

c) metals

d) alloys

 

 

2. Ceramic materials are … in weight.

a) light

b) heavy

c) strong

d) durable

 

 

3. The … of application of products made from clay is very wide.

a) range

b) form

c) class

d) area

 

 

4. Silicate materials … glass, porcelain, enamels and cement.

a) form

b) use

c) consist of

d) include

 

 

5. The ceramic materials … from rock or clay mineral.

a) compound

b) were compounded

c) are compounded

d) have compounded

 

6. The ceramics … as building materials since ancient time.

a) have used

b) used

c) are used

d) have been used

 

 

7. Some ceramic materials can … steel.

a) form

b) cut

c) provide

d) cast

 

 

8. The making of steel depends on the … of ceramics

a) use

b) form

c) property

d) bond

 

 

9. The large oxygen atoms … as a matrix with small metal allows.

a) create

b) serve

c) influence

d) produce

 

 

10. Many articles made of ceramics provided man with …

a) products

b) materials

c) compounds

d) tools

 

 

Unit 4

 

Vocabulary

1. confine – ограничивать
2. continual – непрерывный; постоянный
3. hamper – препятствовать, затруднять, мешать
4. hardly – едва
5. neighbouring – соседний
6. observe – наблюдать
7. occur – происходить, встречаться
8. oscillation – колебание
9. pressure – давления
10. probably – возможно
11. readily – легко, охотно
12. restlessness – подвижность; беспокойство
13. restricted – ограниченный
14. slight – незначительный
15. suspend– вешать, подвешивать
16. therefore – следовательно
17. vessel – сосуд

 

II. Выполните упражнения

  1. Составьте 15 вопросов к тексту
  2. Найдите английские эквиваленты к русским сочетаниям

1. мощный микроскоп

2. постоянное движение

3. под наблюдением

4. независимое существование

5. высокая скорость

6. сила притяжения

7. изменять объем

8. постоянная форма

9. оказывать давление

10.друг с другом

 

a. under observation

b. independent existence

c. high speed

d. continual movement

e. powerful microscope

f. with each other

g. to exert pressure

h. the attractive force

i. to vary one's volume

j. a fixed shape


  1. Прочитайте, переведите однокоренные слова и определите, к какой части речи они относятся

observe, observation; rest, restless, restlessness; suspend, suspen­sion; collide, collision; hard, hardly, hardness; power, powerful; at tract, attractive, attraction; compress, compressible

 

4. Переведите следующие предложения и используя данные фразы, выполните задания

 

As for as I know/understand
According to the text

As for as … is concerned

 

It’s interesting to know/to find out

To my mind
I have a feeling
Give an account of the characteristic properties of matter in the solid, liquid and gaseous states.

What is meant by the statement "the eternal restlessness of matter"?

Give an example of the "Brownian movement". What light do your examples throw upon the nature of matter?

 

  1. Составьте свой диалог, используя информацию текста, на одну из следующих ситуаций

- Two student are discussing the lecture about matter

- A student discussed his/her paper with the supervisor

 

III.Control text

 

Прочитайте и переведите текст

 

That matter may exist in three physical states (solid, liquid and gas) is common knowledge. It is usually possible to change matter from one state to the other by changing its temperature. For instance, a piece of ice is called a solid; it may melt and form a liquid; as it evapo­rates, liquid water changes into a vapour, i. e. into the gaseous state.

Many kinds of matter, like water, can be obtained in each of the three states; for some, however, extraordinary means have to be used in order to produce one, or even two of the states; and for others, only two states are known or can be produced.

Common salt, for example, exists normally as a solid; at a temper­ature of several hundred degrees, it can be liquefied; and at still higher temperature it is converted into vapour. Carbon, a solid under normal conditions, can be vaporized, but it has never been liquefied.

Solids have both a definite volume and a definite shape. Liquids, too, have a definite volume, but they take the shape of their containers.

Gases have neither a definite shape nor a definite volume. A chemist must have a thorough knowledge of the states of matter and of physical laws that govern the behaviour of matter in various states.

That all matter is composed of molecules is known to everybody. The question which must be answered, then, is: if all matter is com­posed of molecules, what is the essential difference between the states of matter? The answer to this question is that the essential difference between these states is the relative quantities of energy molecules possess in different states.

 

Ответьте на вопросы, используя информацию текста

1. What is the difference between a thing and a stuff?

2. Can you tell a thing from a stuff: brass, bottle, atmosphere, chair, pan, boiled egg, glass, ornament, wood, sea water, air, plastics, toy soldier? Match a thing with the stuff it is made of.

3. Can we call a stuff matter? Explain why.

Test 4

 

1. Matter is not only … animals and plants

  1. Unloving
  2. Living
  3. Converting
  4. Occurring

2. Matter is constantly undergoing …

  1. Forms
  2. Mixtures
  3. Classes
  4. Changes

3. Forms of matter may change, but matter itself is neither … not created

  1. Improved
  2. Appeared
  3. Destroyed
  4. Referred

4. The … theory explains what matter is built of

  1. Dalton
  2. Experimental
  3. Molecular
  4. Atomic

5. The movement of molecules … by Robert Bromn

  1. Was studied
  2. Studied
  3. Has been studied
  4. Had been studied

6. The molecules of a … can more freely

  1. Gas
  2. Matter
  3. Liquid
  4. Solid

7. The motion of particles … energy

  1. Refer do
  2. Depends on
  3. Consist of
  4. Slow down

8. Sulphur is chemically very closely related to …

  1. Oxygen
  2. Hydrogen
  3. Carbon
  4. Rater

9. The states of matter are …

  1. Few
  2. Many
  3. Some
  4. Any

10. Cooling a gas into a liquid makes it possible … it more effectively

  1. To keep
  2. To use
  3. To hold
  4. To store

 

Unit 5

 

I Прочитайте и переведите текст

 

Radioactivity

The discover of natural radioactivity by the French researcher Henri Becquerel ushered in a new era in science and technology. This phenomenon is based on the principle that substances occurring in nature, such as uranium and radium, are transformed into other chemical elements, independently of influences from outside, emitting different kinds of radiation which blacken a photographic plate as this is done by the rays of light.

In the decades following this discovery thousands of scientists in many countries of the world have systematically investigated the essence and the application of radioactivity and of the radiation emitted by radioactive nuclides.
The basic practical and theoretical work done by the Curies, the work by E. Rutherford who achieved an artificial nuclear transformation, the development of apparatus for the detection of radioactive nuclides by Geiger and Muller, the discovery of neutron by the English physicist J. Chad-wick, the discovery of the artificial radioactivity by the Curies and the discoveries of some other scientists are the milestones in the history of radioactivity.
The field of application of radioactive nuclides in chemistry, physics, biology, agriculture, medicine and industry has rapidly expanded.
One of the most interesting fields of applications of radioactivity is the determination of the age of carbonaceous materials, that is materials containing carbon, by measurement of their radioactivity due to carbon 14.
This technique of radiocarbon dating permits the dating of samples containing carbon with an accuracy of around 200 years.
At the present time the method involved can be applied to materials that are about 25,000 years old.
Today the range of application of radioactive nuclides comprises all branches of research work. Thus, for example, certain medical examinations call for short lived radioactive nuclides in order that the human organism should not be exposed too long a period of time to radiation, whereas a radioactive nuclide which excites the luminescent material should have a long half-life.
Investigations into the reaction mechanisms in chemistry, researches in the field of physics, the explanation of vital processes in plants, animals and man, diagnostics of diseases of the human body, the testing of metallic and ceramic materials are but a few fields of science and technology which today, 91 years after the discovery of radioactivity, cannot dispense with radioactive nuclides and the radiation emitted by them.
It should be added that a considerable number of research problem's has only become soluble by the use of radioactive nuclides.

 

Vocabulary

1. application – применение
2. to emit - излучать
3. ray – луч
4. to occur – происходить
5. artificial – искусственный
6. milestone – веха
7. to measurement – измерение

 

8. to permit – позволять
9. sample – образец
10. to comprise – охватывать
11. investigation – исследование
12. disease – болезнь
13. soluble - разрешимый
14. vital – низший
15. to expose – подвергать

 

 

II Выполните упражнения

1. Ответьте на вопросы

1. Who discovered the phenomenon of radioactivity? 2. What is the phenomenon of radioactivity based on? 3. What are the milestones in the history of radioactivity? 4. Where can radioactivity be applied? 5. What is the most interesting field of applications of radioactivity? 6. Where are radioactive nuclides applied now?

 

2. Откройте скобки, выбрав правильную форму предлога, объясните почему и переведите предложения.

1. A positively (charging, charged) particle having the mass of the electron was discovered in 1932. 2. The scientist found that X-rays (produced, producing) were complex. 3. According to this theory (dealt with, dealing with) atomic structure the nucleus is a very small, compact, central part of an atom. 4. Oppositively (charged, charging) particles exert forces of attraction on one another. 5. Elements (composed, composing) of atoms containing only one or two valence electrons usually form positive ions. 6. (Investigated, investigating, having investigated) this phenomenon the scientists can make some important conclusions. 7. The work (doing, done) by these research-workers resulted in many new discoveries. 8. The ions (involving, involved) can be used as a highly sensitive detector of radiation. 9. The investigation (followed, following) by many experiments was of great importance. 10. The nuclei (formed, forming) in this reaction are unstable.

3. Переведите предложения, объясните значение глагола «to hare».

1. The laboratory of general chemistry has many benches with a number of drawers. 2. A first-year student has to carry out a number of experiments in the laboratory of general chemistry. 3. This term the students have carried out a number of experiments. 4. These substances have very low solubility. 5. They have to find out the solubility of this substance. 6. They have found the solubility of this substance and now can investigate its properties better. 7. This metal has found wide application both in industry and in agriculture. 8. They have to raise the temperature greatly as the mixture doesn't boil. 9. Hydrogen peroxide has been heated. 10. Hydrogen peroxide has a lower vapour pressure than water.
11. The evaporation has to be carried out in the water bath. 12. This crucible has been used for heating some solutions. 13. This solution has an unpleasant odour, he has to open the window. 14. A rombic sulphur has to be kept at a temperature of 96°C. 15. It is necessary to purify water, you will have to pass it through porous paper. 16. It has to be noted that chlorine dioxide reacts with water and yields a mixture of chlorous and chloric acid. 17. It has been already noted that hydrogen is found in the free state only in minute quantities.

4. Поставьте все типы вопросов к предложениям, переведите предложения

1. Much could be (writing, written) about the application of nuclides. 2. Many experiments have been (carrying out, carried out) in the field of radioactivity. 3. The work (doing, done) by the scientists was of great significance. 4. Many of the above-mentioned applications of radioactive nuclides or of the radiation (emitting, emitted) by them are directly or indirectly connected with industry. 5. A mechanical method was (substituting, substituted) by a new one. 6. This type of radiation consists of a current of positively (charged, charging) particles. 7. This discovery (following, followed) by many experiments was of great use to chemists. 8. The two substances (investigating, investigated) were homogeneous. 9. The man (speaking, spoken of) was thе first to discover this phenomenon.

5. Сделайте письменный пересказ текста на английском языке

III. Control text

Прочитайте и переведите текст

Radiation exerts two opposing effects on polymers. On the one hand, it breaks up the polymer molecules into smaller pieces. On the other, it causes liberation of a hydrogen atom from each of the two adjoining molecules with formation of a link between the two molecules (cross-linking). The existence if cross-links in a polymer makes the material tougher and higher melting and is very desirable for certain applications.

The cross-linking of polymers by radiation has been much studied. The irradiation of any organic compounds results in breaking of CH bonds, leaving free bonds on the carbon atoms while the hydrogen atoms go off together in pairs to form hydrogen gas. In a liquid the resulting free radicals can diffuse as a whole through the solution and eventually meet together and combine. In a solid polymer it is not clear how these centers get together. One proposed mechanism is that a hydrogen atom from a neighbouring carbon will pop into the vacated hydrogen space, producing a new free bond on the atom adjacent to the original free bond position. This process will continue, with the free bond flowing up and down the chain, until the free bond happens to find itself next to a free bond formed on the adjacent molecule which is likewise traveling up and down. Another mechanism, possible perhaps only with amorphous polymer, is that the long-chain molecules as a whole may move with respect to one another until the free bonds find themselves in proximity.

Whatever the mechanism of cross-linking may be, the result is of commercial value.

Озаглавьте текст и объясните свой выбор. Напишите 5 предложений, передающих основное содержание текста.

Test 5

 

1. The nuclei of hydrogen and oxygen are absolutely…

Large

Strong

Stable

Weak

 

2. The Curies discovered the … radioactivity

  1. Artificial
  2. Nuclear
  3. Natural
  4. Uranium

 

3. The discovery of radioactivity … а number of questions.

Rise

Raised

Rose

Raise

 

The discovery of natural radioactivity … by Henry Becquerel

  1. Was being made
  2. Was made
  3. Has been made
  4. Had been made

 

The field of application of radioactive nuclides has rapidly…

  1. Increased
  2. Improved
  3. Discovered
  4. Expanded

 

Uranium and radium are … into other chemical elements

  1. Transformed
  2. Emitted
  3. Based
  4. Done

 

Blackening a photographic plate is done by the … of light

  1. Ways
  2. Atoms
  3. Rays
  4. Movement

 

Radiation exerts two opposing effects on …

  1. Elements
  2. People
  3. Atoms
  4. Polymers

 

The irradiation of organic compound … in breaking of CH bonds

  1. Leads
  2. Continue
  3. Results
  4. Makes

 

The range of application of radioactive nuclides … all branches of research work

  1. Includes
  2. Comprises
  3. Consists
  4. Makes

Unit 6

I. Прочитайте и переведите текст

There is a tradition among physical chemists to regard the properties of liquids as essentially invariant. When comparing them with gases we can see that they are only slightly com­pressible.

Having carried out a number of investigations the scien­tists made a very interesting discovery, i.e. a new stable form of water having the density almost one and a half times that of ordinary water was obtained. This water was named Water II. Having examined its properties they found out that its index of refraction was equal to about 1.48 to 1.49. But when Water II was diluted with ordinary water (Water I) this value dropped to the value for pure water, i.e. 1.33. Having contin­ued their work the scientists stated that the density of Water II was equal to that of pure water. Then it was very important to learn the stability of the molecules of Water II and the forces responsible for their stability.

Some scientists suggested the possibility that on Venus wat­er exists mainly in the form of Water II. This question attracted the attention of many scientists and will be discussed in future.

Water is hydrogen oxide, a compound of hydrogen and oxy­gen. It can be made if hydrogen or a hydrogen-containing substance are burnt in air or oxygen.

Most of the world's water is liquid, but an important frac­tion is solid as ice and snow.

Many mineral substances contain water of crystallization (e.g. copper sulphate) and in the atmosphere there are millions of tons of water vapour. Clouds consist of minute droplets of water or crystals of ice.

Water dissolves a very large number of substances and is the most important solvent. It does not dissolve greasy, fatty substances or most plastics.

Having found the composition of water, the scientists could Investigate its properties. It was stated that ordinary water is impure, it usually contains dissolved salts and dis­solved gases, and sometimes organic matter.

For chemical work water is to be purified by distillation. Pure water is colourless, tasteless and odourless. Rain water formed by the condensation of water in the air is nearly pure water, containing only small propoftions of the dust and of dissolved gases.

Having examined the properties of water, the chemists found that physical properties of water can be used to define many physical constants and units.

The freezing point of water (saturated with air at 1 atm pressure) is taken as 0°C and the boiling point of water at 1 atm is taken as 100°C.

The unit of volume in the metric system is chosen so that 1 ml of water at 3.98°C (the temperature of its maximum density) weighs 1.000 g/cm3.

So water is one of the most important of all chemical sub­stances. It is a major constituent of living matter and of the environment in which we live.

Vocabulary

1. superdence – сверхплотная
2. to regard – рассматривать
3. hence – следовательно
4. negligible – незначительный
5. to compare – сравнивать
6. slightly – слегка
7. vit (namely) – а именно
8. choice – выбор

 

9. to cause – быть причиной
10. stable – постоянный
11. to dilute – растворять
12. to drop - капать
13. to assume - предполагать
14. impact – влияние
15. to burn – жечь, сжигать
16. to purity – очищать
17. to saturate - насыщать
18. to choose – выбирать

 

II. Выполните упражнения

1. Дайте русские эквиваленты к следующим словам, словосочетаниям и химическим терминам. Где конкретно они используются в тексте, а какие нет?

nouns: 1. condition, 2. current, 3. hydrogen oxide, 4. importance, 5. point of view, 6. quarter, 7. surface, 8. vapour

verbs: 9. burn, 10. cool, 11. cover, 12. heat

adjectives: 13. artificial, 14. dangerous, 15. marked, 16. strict

adverbs: 17. commonly, 18. exactly, 19. in this way

conjunctions: 20. either... or.

2. Подберите к словам из упр. 1 синонимы, данные ниже

a) to warm up к) water

b) usually 1) viewpoint

c) stream m) synthetic

d) steam n) to fire

e) to chill o) rigorous

f) hazardous p) to hide

g) the 4th part of a whole q) significance

h) noted r) the outer part

i) state s) precisely
j) thus

3. Найдите антонимы в А и В

А В

1. the commonest a) impossible

2. like b) the most unusual

3. simple c) old

4. usually d) common

5. new e) few

6. single f) eptionally

7. many g) to lose

8. decomposition h) natural

9. to obtain i) unlike

10.possible j) integration

11.easy k) complicated

12.dangerous 1) secure

13.artificial m) lenient

14.strict n) difficult

4. Откройте скобки, выбрав правильную форму предлога, переведите предложения

1. When (heating, having heated) this substance, one should be very careful. 2. (Investigated, having investigated, investigating) all the properties of new water, they could understand the mistery of silvery clouds. 3. The (dissolving, dissolved, having dissolved) materials may be soluble solids, liquids or gases. 4. Water (using, used, having used) in steam boilers, should be free from substances that cause corrosion. 5. (Purified, having purified, purifying) the water from the substance that cause corrosion, we can use it in steam boilders.

5. Поставьте 15 вопросов к тексту

III. Control text

Прочитайте и переведите текст

One of the most striking properties of water is its ability to dissolve many substances, forming aqueous solutions. Solutions are very important kinds of matter – important for industry and for life. The ocean is an aqueous solution that contains thousands of components: ions of the metals and non-metals, complex organic ions, many different organic substances. It was in this solution that the first living organisms developed, and it was from it that they obtained the ions and molecules needed for their growth and life. In the course of time organisms that were evolved could leave this aqueous environment, and move out onto the land and into the air. They achieved this ability by carrying the aqueous solution with them, as tissue fluid, blood plasma, and intracellular fluids containing the necessary supply of ions and molecules.

The properties of solution have been extensively studied, and it has been found that they can be correlated in large part by some simple laws.

Water not only is the most widely used of all solvents, but also, of all liquids, it most nearly approaches being the “universal solvent”. Every substance is probably soluble in water to some extent, although in many cases the solubility is so small that it is almost imperceptible. Thus, a saturated solution of barium sulphate contains less than a quarter of a milligram of solute per litre, and the solubility of silicon dioxide (quartz) – is even smaller than this. Yet, water that is allowed to remain for a long time in a quartz vessel must eventually become saturated with quartz; a saturated solution of this substance is so extremely dilute, however, that many litres of it would have to be evaporated to dryness in order to yield a visible residue. Such substances as barium sulphate, silver chloride, quartz, glass, mercury, and cellulose are usually considered as “unsoluble” in water; but this term, it must be remembered, is merely a relative one, and it would be more accurate to say that their solubility is exceedingly small.

 

-Передайте основное содержание текста в нескольких предложениях.

-Прочтите предложения и скажите, соответствуют ли они содержанию текста. Если нет, исправьте их.

1. Water can dissolve a great number of substances. 2. Solutions arc important in industry, but not in life. 3. A lot of components are dissolved in the ocean water.

4. The first living organisms developed in water and on the land and then moved into the air. 5. There are no laws common to all the solutions and the properties of each solution are studied separately. 6. Every substance is soluble in water to some

 

Test 6

1. One of the way to purity water is … it

  1. to heat
  2. to boil
  3. to evaporate
  4. to distillate

 

 

2. Water is the most … compound

  1. usable
  2. abundant
  3. universal
  4. pure

 

 

3. The ground water contains a great deal of …

  1. impurities
  2. mixtures
  3. microbes
  4. salts

 

 

4. When water vapour condences to liquid water, energy …

  1. releases
  2. will release
  3. has released
  4. is released

 

 

5. Water is a major … of living matter

  1. constituent
  2. part
  3. form
  4. substance

 

 

6. Water … a very large number of substances

  1. evaporates
  2. saturates
  3. dissolves
  4. drops

7. … water is odourless and tasteless

  1. ground
  2. pure
  3. distillated
  4. sea

 

 

8. Natural water have taste because of the presence of … substances

  1. purified
  2. distillated
  3. evaporated
  4. dissolved

 

 

9. Several common units of measurement … in terms of the properties of water

  1. are used
  2. are made
  3. are defined
  4. are discovered

 

10. Most of the world’s water is …

  1. liquid
  2. solid
  3. gaseous
  4. vapour

 

Unit 7

 

Liquids

The liquid state occupies an intermediate position between the gaseous and solid states, liquid having a definite volume but no definite shape.

Like a gas, a liquid can take the shape of any vessel in which it is put, but in contrast to a gas, a definite quantity of liquid is required for filling the vessel. A liquid can’t be compressed so much as a gas because it’s molecules are already close together, large pressure producing small changes in volume.

Increasing the temperature increases the kinetic energy of all molecules.

The change of a liquid into the gaseous or solid states being dependent upon the kinetic energy of the molecules, which in turn is dependent upon the temperature, there are definite temperature characteristics for most liquids at which these changes occur. The are known as transition temperature.

If we place one liquid layer carefully on top of a layer of a more dense liquid in which it is soluble, and set the vessel where it won’t be disturbed, we shall see that two liquids begin gradually mixing. It is also to be taken into the consideration that all liquids do not flow with the same ease, water, alcohol, gasoline flowing easily, while heavy oil, glycerine flowing very slowly.

When a liquid flows, layers of molecules begin rubbing over each other, friction being generated by this rubbing of layers of particles. The greater the friction, the slower is the flow. A liquid which resist flowing, or resist the action of any other deforming force upon it results in a homogenous solution. We give this example for illustrations that the molecules of a liquid diffuse, though much more slowly than do those of a gas.

The molecules of a liquid are much closer together than they are in a gas, because of the greater relative strength of attraction, the density of liquids being much greater. Naturally as the volume of a liquid begins varying with temperature it’s density will also start varying with temperature.

It should be noted that the closeness of the molecules also is known as viscous, the opposite of viscosity being fluidity. Viscosity diminishes and fluidity increases with temperature.

 

 

Vocabulary

  1. intermediate – средний, промежуточный
  2. vessel – сосуд
  3. to compress – сжимать
  4. layer – слой
  5. to disturb – нарушать
  6. mean – средний
  7. gradually – постепенно
  8. in turn – в свою очередь
  9. to rub – тереть
  10. friction – трение
  11. viscosity – вязкость
  12. fluidity – текучесть
  13. to enable – позволять
  14. surface – поверхность
  15. dense – плотный, густой
  16. to flow – течь
  17. density – плотность
  18. to diminish – уменьшаться
  19. velocity – скорость
  20. to escape – улетучиваться
  21. to fill – наполнять

II. Выполните упражнения

 

1. Ответьте на вопросы

1. What position does liquid state occupy? 2. What shape does liquid take? 3. Is it possible for a liquid to be compressed? 4. Why is it impossible? 5. What does the change of a liquid into the gaseous or solid states depend on? 6. What will happen if we place one liquid layer on top of a layer of a more dense liquid in which it is soluble? 7. Do all liquids flow with the same ease? 8. What is the friction generated by? 9. Why are the molecules of a liquid much closer together than those of a gas? 10. What is evaporation?

 

2. Переведите предложения. Определите функцию герундия в предложении и его форму.

1. Discussing the topic helped both of us to understand it better. 2. Professor N’s participating in this conference attracted many other scientists. 3. His having made detailed notes at the lecture helped him to successfully pass the examination. 4. Our article being accepted in the Journal of Analytical Chemistry is a great honour to us. 5. There is no saying that the difference in temperature is too great. 6. Sometimes, preparing substances requires less skill than keeping them. 7. Solid bodies have the property of keeping their shape without supporting of a vessel. 8. Upon being heated, the molecules begin moving very quickly. 9. Without being treated this substance cannot be used. 10. At last our research-workers succeeded in getting good results. 11. By using this law we define a unit charge of electricity.

 

III. Control Text

Прочитайте и переведите текст.

 

When iodine crystals are heated to 114º C. they melt forming liquid iodine. The temperature at which the crystals and the liquid are in equilibrium – that is, at which crystals have no tendency to melt or the liquid has no tendency to freeze – is called the melting point of the crystals, and the freezing point of the liquid. This temperature is 114º C for iodine.

Liquid iodine differs from solid iodine (crystals) mainly in its fluidity. Like the solid, and unlike the gas, it has a definite volume (1g occupies about 0.2 cm³), but it does not have a definite shape: instead, it fits itself to the shape of the bottom part of its container.

From the molecular viewpoint the process of melting can be described in the following way. As a crystal is heated, its molecules are increasingly agitated, and move about more and more vigorously, but at lower temperature, this thermal agitation does not carry any one molecule any significant distance away from the position fixed for it by the arrangement of its neighbours in the crystal. At the melting point the agitation finally becomes so great that it causes the molecules to slip by one another and to change somewhat their location relative to one another. They continue to stay close together, but do not continue to retain a regular fixed arrangement. Instead, the grouping of molecules around a given molecule changes continually, sometimes being much like the close packing of the crystal, in which each iodine molecule has twelve has only ten or nine or eight near neighbours. Thus, a liquid, like a crystal, is a condensed phase, as contrasted with a gas, the molecules being piled rather closely together; but whereas a crystal is characterized by regularity of atomic or molecular arrangement, a liquid is characterized by randomness of structure. The randomness of structure is usually the reason why the density of a liquid is somewhat less than that of the corresponding crystal.

Дайте подробные ответы на вопросы:

1. What is the melting point of a substance? 2. What are the characteristic features of a gas? 3. What does the physical state of a substance depend on?

Обсудите следующие темы в 4-5 предложениях:

  1. Liquids from the molecular point of view.
  2. Properties of liquids

 

Test 7

1. If not in a container the liquid … on the surface.

a) leaves for

b) spreads out

c) touches upon

d) takes up

 

2. A liquid being heated, the molecules … the force of attraction.

a) reach

b) remain

c) form

d) overcome

 

3. Liquids more than solids …smell.

a) give on

b) give off

c) give up

d) give out

 

4. The temperature at which the molecules leave the surface is the …

a) freezing point

b) boiling point

c) melting point

d) heating point

 

5. One of the main properties of liquid is its …



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