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changes. 3. Common salt was acted upon by sulphuric acid and hydrogen chloride was produced. 4. His work in this field can be relied on. 5. They were told about the new discoveries in oil production. 6. The change in colour was followed by the change of other properties. 7. Fermi is looked upon as an outstanding physicist of our time. 8. The results of their investigation can be referred to. 9. I was asked to attend his lecture on chemistry. 10. Liquid solutions will be dealt with in this chapter. 11. The qualitative examination of this compound is followed by the quantitative one.

Ex.4. Choose the Russian equivalents from the right column:

LESSON Ill.

Notes on the Text

1.to be alike - 6blTb nOA06HbIM, nOXO>K~M

2.a great number of - MHoro, 60Ilbwoe KOIl~yeCTBO

3.besides - KpoMe, nOM~MO

4.in good order - B xopoweM COCTO~H~~, B xopoweM nop~AKe

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5. in addition to - KpoMe, nOMVlMo, B Aonol1HeHVle K

T EXT. LABORATORY

All the laboratories of inorganic chemistry are almost alike. These are large rooms where both students and research-workers carry out their experimental work.

Modern laboratories of inorganic as well as organic and analytical chemistry are provided with gas and running water. Every laboratory is to be provided with a ventilating hood for the escape of both harmful and unpleasant vapours and odours. Every laboratory has to be lit up very well.

There are many laboratory benches with a great number of drawers in very laboratory. Different apparatus devices as well as materials are to be kept in them. Besides we can see many shelves and cases for containers with chemicals.

On every laboratory bench one can see test-tubes, flasks, beakers, funnels, evaporating dishes, weighing bottles. All this glassware should be kept in good order.

Various burners serve for producing flames. Bunsen burner is to be mentioned among them.

Different crucibles are to be employed when heating of solution and igniting of materials are to be carried out. Crucibles are usually made of quartz, porcelain and iron. In addition to these crucibles, there are platinum crucibles in some laboratories, but they are used very seldom.

Every laboratory should be equipped with different kinds of apparatus. Everything in the laboratory is to have its definite place.

Experiments in the Laboratory

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Many experiments can be carried out in the laboratory of inorganic chemistry. Thus, if we want to obtain hydrogen chloride (Hel), which is often referred to as a hydrochloric acid gas, it is necessary to pour some sulphuric acid through a tube over the crystals of sodium chloride, in a flask. The flask is to be heated. On warming the flask, the hydrogen chloride is expelled as a colourless gas with a suffocating odour. It produces heavy clouds of white fumes when it comes in contact with the moist air of the room.

It is soluble and it cannot be collected over water as are oxygen and hydrogen. It is much heavier than the air and may be passed through a glass tube to the bottom of a bottle. If we dissolve some of the gas in water, the solution has a sour taste, reddens blue litmus, reacts with zinc, etc.: it is hydrochloric acid. When all the sodium chloride originally present in the flask has been transformed, the reaction is complete. The flask then contains a salt called sodium acid sulphate (NaHSO 4 ) together with unchanged excess of sulphuric acid.

* * *

Nitric acid may be prepared by the reaction of concentrated sulphuric acid with sodium nitrate.

In the laboratory method, a mixture of sodium nitrate and concentrated sulphuric acid is heated in a glass retort. Nitric acid is boiled out of the mixture and is condensed:

NaN0 3 + H2 SO 4 = HN0 3 + NaHSO 4

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Remember the following words and word combinations:

Ex.1. Compare the following pairs of sentences and translate them into Russian:

1.They washed glassware well. Glassware was washed well.

2.The professor referred to this new book.

The new book was referred to by the professor.

3.The student sent his friend to the library. The student was sent to the library.

4.The students have answered all the questions.

The students have been answered all the questions.

5.He spoke much about this new invention. He was much spoken of.

6.He insisted on these conditions.

These conditions were insisted on (by him).

7.Large quantities of sulphur have been produced recently at the plants.

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They have produced large quantities of sulphur recently.

Ex.2. Translate the following sentences into Russian:

1.He was told to be in time. 2. She was asked to help him.

3.They were sent to the plant. 4. He was sent for. 5. The professor was sent for. 6. The speaker has been listened to with great interest and attention. 7. The new discovery is much spoken of in our Institute. 8. They will be given a very important task.

Ex.3. Translate the following sentences paying attention to the meanings of the verbs "to have":

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'tboil. 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 waterbath. 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

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and chloric acid. 17. It has been already noted that hydrogen is found in the free state only in minute quantities.

Ex.4. Translate the following sentences paying attention to the meanings of the verb "to be":

1. This SUbstance is colourless and odourless. 2. Liquids which are not appreciably soluble in each other are called immiscible liquids. 3. Many new research institutes are being built in our country. 4. They are discussing a very important problem dealing with the development of new branches of chemistry. 5. The volume of an object increases when it is heated. 6. There is a large new laboratory in our Institute. 7. This experiment is to be carried out again, the results are wrong. 8. The meeting of our Chemical Society is to take place tomorrow at 5 o'clock. 9. He is to graduate from the ChemicoTechnological Institute in 2008. 10. This solution was to be heated in a porcelain crucible. 11. The solution was heated and evaporated. 12. The glassware is to be washed very thoroughly when the experiment is over.

Ex.S. Choose the Russian equivalents from the right column:

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LESSON IV.

Notes on the Text.

1.in order to - AI1~ Toro 4T06bl

2.that is (i.e.) - TO eCTb

3.to take into account - nplllHIIIMaTb BO BHIIIMaHlIIe

T EXT. THE MEASUREMENTS IN CHEMISTRY.

In order to understand the quantitative relationships which exist between various kinds of matter, the chemist who is interested in matter and the changes which it undergoes, has to measure the quantities of matter with which he works, that is since mass is the measure of the quantity of matter, he is to measure mass. The measuring device the chemist is to employ in this determination should be the balance.

Since for every chemical change there is always accompanying energy change which the chemist has to take into account, the calorimeter and the thermometer have to be used.

The chemist usually employs graduated cylinders, burettes, pipettes and volumetric flasks for the measurements of volumes of liquids, and the gas burette for the measurement of volumes of gases.

The chemist employs the barometer if he has to measure the pressure.

The analytical chemist and the physical chemist

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employ such devices as calorimeters, polarimeters, refractometers and a number of electrical devices.

If the chemist is to examine very small samples of matter, he should use a microscope. The microscope is an instrument which by the combination of lenses permits man to see objects which are too small to be seen with a naked eye. It is an instrument which is useful in many sciences and which, although more frequently used in a qualitative way, can also be used quantitatively.

The Metric System.

The fundamental unit of the metric system is the metre. The millimetre and centimetre are the units which the chemist uses very frequently in his work.

If one is to measure extremely short distances, the micron is to be used.

The unit of mass is the gram, milligram or the kilogram. The unit of the heat measurement is the calorie.

Remember the following words and word combinations:

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