title: Санкт-петербургского государственного университета высшее профессиональное образование т. А. Степанова, И. Ю. Ступина - бет 100

text:
know what substanccs wc arc going to obtain in a reaction. 20. Tem
perature docs not depend on how much matter is present. 21. It is
ncccssary that the temperature should be kept constant. 22. The supervisor
insisted that wc should learn the instruction. 23. It is desirable .that
Dr. N should speak at the confcrencc. 24. It is essential that oxidation
state should be known. 25. Our supervisor proposed that wc should write
a joint paper. 26. The tcachcr advised that the student should consult a
rcfcrcncc-book. 27. It was ncccssary to prove whether the conclusion
that was made in the paper was right. 28. It was my collcaguc who
rccommcndcd that the pressure o f the reading substanccs should be
increased. 29. Much depends on what the conditions of a reaction are.
30. Sometimes it is difficult to decide what term should be used, bccausc
there is no uniformity in the nomenclature.
Ex. 10. Translate the sentences into English.
1. На конференции 1948 года было принято название «шкала
Цельсия» для стоградусной шкалы температур. 2. По шкале Цель
сия вода замерзает при 0°С, кипит при 100°С. 3. Следует отмстить,
что это название было выбрано по аналогии с такими названиями,
как шкала Кельвина, шкала Фаренгейта и др. 4. Это решение было
принято в интересах единообразия при практическом применении.
5. Термин «шкала Цельсия» более точен, так как шкала Кельвина —
это тоже стоградусная шкала. 6. В англоязычных странах в повсед
невной жизни продолжают пользоваться шкалой Фаренгейта.
7. Шкала Реомюра имеет 80 делений между точкой замерзания и
точкой кипения воды.
Ex. 11. Answer the following questions:
1.
What problems were discusscd at the confcrencc in 1948? 2. What
name was adopted for the temperature scalc devised by Celsius? 3. What
was the reason for choosing a single name for the scalc? 4. Why was the
name “Celsius” considered preferable? 5. What other name for this scalc
do you know? 6. What other temperature scalcs do you know? 7. What
temperature scalcs arc used in Russia?
Достарыңызбен бөлісу:


title: Section II - Санкт-петербургского государственного университета высшее профессиональное образование т. А. Степанова, И. Ю. Ступина

text:
Упр. 4. Составьте план текста.
Упр. 5. Прочтите предложения н скажите, соответствуют ли онн
содержанию текста. Если ист, исправьте их.
1. More than a century ago scientists noticcd the dependence between
the temperature and the volume of a gas. 2. The temperature at which the
volume o f the gas sample would become zero was named the absolute
zero. 3. Hie scalc according to which the absolute zero is taken to be 0° is
the International Standard temperature scalc. 4. The triple point of water
is the temperature when vapourization begins. 5. The temperature by the
Kelvin scalc is the temperature by Celsius scalc plus 273.15°. 6. Gas
thermometer is used for ordinary measurements. 7. Gas thermometer is a
convenient instrument. 8. This dcvicc is highly accurate.
Ex. б. Найдите в тексте описание того, как ученые пришли к кон
цепции абсолютного нуля, переведите эти предложения на русский
язык.
Достарыңызбен бөлісу:


title: Section Ш - Санкт-петербургского государственного университета высшее профессиональное образование т. А. Степанова, И. Ю. Ступина

text:
Model: —
A question.
—
A clarifying question.
—
An answer.
—
A statement.
Ex. 3. Make up short dialogues according to the model.
Example: — I didn’t like all the subjects when I was a pupil.
— What subjects didn’t you like?
— English, for example.
— As for me, I didn’t like history.
Ex. 4. Give detailed answers to the questions.
1. What temperature scales do you know? 2. How was the International
Standard scalc adopted? 3. What are the most widely used temperature scalcs?
4. In what way can one convert the temperature from one scalc to another?
5. What instruments arc used for temperature measurements?
Ex. 5. Discuss the following topics:
1. The Problem of Uniformity in Measuring the Temperature.
2. Different Temperature Scalcs.
3. Means of Measuring the Temperature.
WHAT IS IT?
A unit in a temperature scalc.
Достарыңызбен бөлісу:


Lesson 24
ГРАММАТИКА: Повторение тем «Подлежащее» и «Дополнение»
Section I
Ex. 1. Practise your pronunciation.
a) recognize ['rekagnaiz], relative [‘relotiv], carefully [‘keofuli], determine
[df t
3
:min], electrolysis [ilek'trohsis], unique [ju:'mk], subsequent ['sAbsikwont],
aqueous ['eikwios], observation [.obzs'veijbn], isolate [’aisolctt], phase [fcizj,
hybridize ['hatbndaiz]
. b) i s j burnedJn\air, 'weight^ofNoxygen, the a'mount^ofshydrogen,
withy'thesejobser'vations, 'neighbouring^'water Smolccules
c) 'Water was 'thought by the/"ancicnts | to be an\clcmcnt.
Ex. 2. Pay attention to the structure of the following words. Translate
them into Russian.
a) undergo, underestimate, underdeveloped, undergraduate, underground,
underline, understand
b) misunderstand, misadvise, misbehave, miscalculate, misconccption,
mishandle, mishear, misinform, mispronounce, mistake
c) semiautomatic, semiconductor, semiannual, semifluid
б Схемном
161
1. Combustion is a chcmical reaction which takes place with the evolution
of both light and heat. 2. As to sulphur and oxygen, it should be noted that
both of these elements have allotropic modifications. 3. Which of the two
seasons do you like better— summer or autumn?— As for me, I like both.
4. Solutions arc very important kinds of matter — both for industry and for
life. 5. Both of the substanccs (barium sulphate and silicon dioxide) arc
practically insoluble in water. 6. What is the matter with M and N, they both
arc absent again? 7. Both sodium and potassium belong to the same family
of elements, it is not surprising that they have similar properties.
Ex. 4. Find the predicate, the subject and the object in the following
sentences:
1. Lavoisier first recognized that water is a compound of the two
elements, hydrogen and oxygen. 2. The structure o f water must be
fundamentally different from that o f most other liquids. 3. The
characteristic increase in the density of water with temperature is found to
continue until 4°C.
Text 24 A
The Composition and Structure of Water
Water was thought by the ancients to be an element. Henry Cavendish
in 1781 showed that water is formed when hydrogen is burned in air, and
Lavoisier first rccognizcd that water is a compound of the two elements —
hydrogen and oxygen.
The formula of water is H20 . The relative weights of hydrogen and
oxygen in the substancc have been very carefully determined as 2.016:16.000.
This determination has been made both by weighing the amounts of hydrogen
and oxygen liberated from water by electrolysis and by determining the
weights of hydrogen and oxygen that combine to form water.
Liquid water has a number o f unique properties which indicate that
the structure must be fundamentally different from that of most other
liquids. Thus, water has high melting and boiling points, an unusually
high heat capacity, and shows a characteristic decrease in molar volume
on melting and a subsequent contraction between 0 and 4°C. Quite apart
from the behaviour of aqueous solutions, any proposed structure for liquid
water must be consistent with these observations.
From spcctroscopic studies o f isolated water molcculcs in the gas
phase, it has been shown that the H—О—H bond angle is very nearly
the tetrahedral angle of 105° and the О—H intcmuclcar distance is 0.97E;
the observed dipole moment is 1.87x10 '1* c.s.u.* acting along the biscctor
o f the H—О—H angle.
Ex. 3. Define the meanings of the word both in the following scntcnccs:
* e.s.u. — clcctrostatic unit
162
Bcmal and Fowler in a classical work on the interpretation of these
results, showed that the net clcctronic density distribution was consistent
with such a structure in which, in addition to the two protons carrying
small positive chargcs, there arc also two regions of negative charge. These
four regions of charge, two positive and two negative, could be regarded
as residing at the corners of a tetrahedron. If the oxygen is approximately
sp3 hybridized then two o f the orbitals on the oxygen atom arc used for
bonding the hydrogen atoms and the other two cany the lone pairs of
electrons which can participate in hydrogen bonds to two neighbouring
water molcculcs. In terms of this picture the structure of ice, in which
each molcculc has four nearest neighbours, can be represented in the
following way. The molcculcs arc held together by tctrahcdrally-dirccted
hydrogen bonds which arc essentially clcctrostatic in charactcr. The
structure is an open one rather than a close-packed with a resulting increase
in density. The characteristic increase in density with temperature continues
until 4°C when die cxpcctcd decrease accompanying the increased thermal
energy becomes apparent.
Words and Word-Combinations to Be Memorized
accompany, apart, apparent, aqueous, behaviour, capacity, careful, character,
charge, consistent, dipole, energy, expect, liberate, moment, net, a number of,
observation, partial, participate, positive, region, spcctroscopc, static, unusually
Ex. 5. Give the Russian equivalents for the following:
.
relative weights, determine very carefully, liberate hydrogen, a number
^ of unique properties, heat capacity, the behaviour of aqueous solutions, be
consistent with, spectroscopic studies, the bond angle, the interpretation
of results, in addition to the protons, positive charge, at the comers o f a
tetrahedron, participate in hydrogen bonds, represent the structure, be
electrostatic in charactcr, thermal energy
Ex. 6. Give the English equivalents for the following:
состав воды, на воздухе, признавать, жидкая вода, отличаться от,
высокие точки плавления и кипения, необычно высокая теплоемкость,
в газовой фазе, мсжъядсрнос расстояние, классическая работа, отри
цательный заряд, водородная связь, соседние молекулы воды, струк
тура льда, следующим образом, удерживать вместе, быть каким-л. по
характеру, а не частичное разрушение структуры, увеличение плот
ности, ожидаемое уменьшение, становиться очевидным
Ex. 7. Fill in the blanks with prepositions where necessary.
1. Cavendish ... 1781 showed water to be formed when oxygen is
burned ... air. 2. The relative weights ... hydrogen and oxygen ... the
substancc were very carefully determined. 3. Water ... the liquid phase
has a number... unique properties. 4. The structure ... water is different
163
... th at... m ost... other liquids. 5. It was shown ... spcctroscopic studies
that the H—О—H bond angle is very nearly the tetrahedral angle... 105°.
6. The molcculcs ... icc arc held together ... tetrahcdrally-directcd
hydrogen bonds. 7. These bonds arc essentially electrostatic ... charactcr.
Ex. 8. Translate the scntcnccs into Russian, paying attention to different
functions of the word will.
1.
The laboratory of analytical chcmistry will soon be transferred to a
new building. 2. Heating w ill affcct the state o f water but not its
composition. 3. Other ways of obtaining hydrogen willbc discusscd in the
next chaptcr. 4. Water is usually callcd a universal solvent bccausc it will
dissolve a tremendous number of substanccs. 5. Will you give me your
dictionary for a couplc of days? 6. He went to the university against his
father’s will. 7. There will be no difficulty in making calculations.
Ex. 9. Translate the sentences into Russian.
1.
That air is not a chcmical compound is now known even to children,
but there was a time when it was thought to be an clement. 2. The chcmists
have many problems to solve, particularly environmental ones. 3. One
has to remember that a reaction with the liberation of heat may be
followed by an explosion. 4. It is sometimes not easy to decide what
catalyst should be used. 5. For a number of chcmical processes it is
desirable to use distilled water. 6. To obtain sufficiently pure water is
one of the urgent problems of the day, especially in chcmical and paper
industries. 7. Boiling is one of the simplest ways of purifying water.
8. Barium sulphate is only slightly soluble, one can easily separate it by
means of a filter. 9. They watchcd the temperature rising, but at the
temperature of 69 degrees the proccss stopped. 10. Phosphorus is very
interesting by existing in several allotropic forms. 11. Never take white
phosphorus with bare hands bccausc heat o f the body is enough to ignite
it. 12. It is its activity with oxygen that is the most striking property of
phosphorus. 13. Compounds of silicon arc found to make up about 87 per
ccnt o f the outer layer of the solid earth. 14. Atoms arc generally known
to be electrically neutral. 15. Hydrogen atom is stated to contain no
neutrons. 16. They supposed the substancc to react at room temperature,
but it wouldn’t. 17. Combining the two mixtures may result in an
explosion. 18. To find free chlorinc in nature is impossible bccausc of
its exceedingly high activity. 19. Chlorinc is considered to be a typical
non-metal. 20. For hydrogen to combinc with chlorinc with appreciable
velocity in the dark is possible in the presence of a catalyst. 21. The
experiments show chlorinc to be an activc oxidizing agent. 22. That the
lightest of the alkali metals is lithium can be determined by its position
in the periodic table. 23. One can observe caesium taking fire at ordinary
temperature. 24. Molccular structure of nitrogen allows the properties
of this element to be accounted for. 25. Nitrogen can be made to form
ammonia by use of a suitable catalyst. 26. Whether the hypothesis is
164
true must be verified experimentally. 27. The aim of this experiment is
to show whether sulphuric acid will react with metals. 28. Lomonosov's
being the first who formulated the second law o f thermodynamics is
seldom mentioned. 29. It is heating that forces many reactions to take
place. 30. A great number of elements have been found to have two or
more isotopes.
Ex. 10. Translate the sentences into English.
1. В древние времена считали, что вода— это одни из элементов.
2. Только в конце XVIII столетия было доказано, что вода состоит из
двух элементов — водорода и кислорода. 3. Теперь каждому школь
нику известно, что формула воды — Н20 . 4. Вода в жидком состоя
нии обладает рядом уникальных свойств. S. То, что вода — необычная
ж и д к о с т ь ,
объясняется ее структурой, б. Интересно также изучение
воды в газообразной и твердой фазе. 7. Характерными физическими
свойствами воды можно назвать высокие точки плавления и кипе
ния, а также теплоемкость.
Ex. 11. Answer the following questions:
1. By means of what experiment was it shown that water is a compound?
2. What is the composition of water? 3. What properties show water to be
a unique liquid? 4. In what way can the properties o f water be accounted
for? 5. What did spectroscopic studies of water molcculcs show? 6. In
what way arc the atoms in the water moleculc held together?
Достарыңызбен бөлісу: |


text:
Text 24 В
Прочтите текст про себя (контрольное время ••тения — 4 минуты).
Water
One of the most striking properties of water is its ability to dissolve
many substanccs, forming
aqueous solutions. Solutions arc 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, complcx organic ions, many different organic substanccs.
It was in this solution that the first living organisms developed, and it was
from it that they obtained the ions and molcculcs
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 intraccllular fluids containing the necessary
supply of ions and molccules.
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
substancc is probably soluble in water to some extent, although in many
eases the solubility is so small that it is almost impcrscptiblc. 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 bccomc saturated with quartz; a saturated solution of
this substancc 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
substanccs as barium sulphate, silver chloride, quartz, glass, mercury, and
ccllulosc arc usually considered as “insoluble” in water; but this term, it
must be remembered, is merely a relative one, and it would be more accuratc
to say that their solubility is exceedingly small.
Упр. 3. Передайте основное содержание текста в нескольких пред
ложениях.
Упр. 4. Составьте план текста.
Упр. 5. Прочтите предложения н скажите, соответствуют ли они со
держанию текста. Если нет, исправьте их.
1. Water can dissolve a great number o f substanccs. 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 arc no laws common to all
the solutions and the properties of cach solution arc studied separately.
6. Every substancc is soluble in water to some extent.
166
Упр. б. Найдите в тексте и переведите на русский язык предложе
ния с описанием того, как ведут себя в воде вещества, которые счита
ются практически нерастворимыми.
Достарыңызбен бөлісу:


title: Section III - Санкт-петербургского государственного университета высшее профессиональное образование т. А. Степанова, И. Ю. Ступина

text:
Section III Ex. 1. Respond to the statements and questions, using the following
expressions: / hope so; so it is; it is; it would be wrong to say so; Pm o f the same opinion. 1. I think wc speak too much about water, there arc many other
interesting liquids. 2. Barium sulphate is insoluble in water. 3. The occan
is an aqueous solution, isn’t it? 4. It was in the occan that the first living
organisms developed. 5. Could wc obtain a solution o f quartz? 6. Thus, in
conclusion wc may say that the term “insoluble" in water is not accurate
when wc speak about silver chloride. 7. Water is usually callcd the
“universal solvent”. 8. Soon wc shall lcam the structure o f water and then
wc shall clcarly understand the nature of its properties.
Ex. 2. Translate the sentences into English.
1.
Тысячи компонентов различных веществ растворены в воде оке
ана. — Да, это так. 2. Наверное, прошло много времени, прежде чем
живые организмы вышли из океана на сушу. — Я тоже так думаю.
3. Свойства растворов хорошо известны, и мы тоже скоро будем их
изучать.— Надеюсь. 4. Есть вещества, например, сульфат бария, кото
рые не растворяются в воде.— Было бы неверно так говорить, потому
что он растворяется, только очень мало. 5. Структура воды уникальна.
— Да. 6. Теплоемкость воды необычно высока. — Да, это так.
Ex. 3. Make up short dialogues according to the model.
Model: — A request — A clarifying question. — A statement. — An answer. Example: — Could you help me with my homework?
— What is the difficulty?
— 1 can’t understand this rule.
— Г11 try to explain it to you.__________
Ex. 4. Give detailed answers to the following questions:
1. What can you say about water in nature? 2. What is the composition
of water? 3. What properties make it a unique liquid? 4. What is the structure
of water interesting for?
Ex. 5. Discuss the following topics:
1. The Physical Properties o f Water.
2. The Structure of Water.
3. Water as a Universal Solvent.
WHAT IS IT?
A part of a solution which is present in greater amount.


title: THE ATTRIBUTE - Санкт-петербургского государственного университета высшее профессиональное образование т. А. Степанова,...

text:
In the 17th century, during the infancy of experimental chcmistry, acids and
bases were defined or described on the basis of their behaviour. Titus, bases
were substanccs that neutralized acids, turned plant
dyes blue, had a bitter
taste, and had a smooth or slippery feeling to the skin.
In the 18th century, following the discovery of oxygen by Joseph
Priestley, Lavoisier advanced the idea that oxygen was the acidifying
principle of all acids. Thereafter, the experimental approach was largely
abandoned and emphasis was placed on the composition o f substanccs
instead o f the phenomenological properties. The development o f the
hydrogen theory of acidity and Faraday’s studies of electrolytic conductance
in the early 19th century led logically to the watcr-ion theory proposed by
Arrhenius. By this conccpt a base may be defined as any hydroxy compound
which gives hydroxyl ions in water solution. Neutralization then involves
the combination of hydroxyl ions with hydrogen formed by the acid,
producing water and incidentally a salt. The role of solvent as an ionizing
medium for acid-base reactions was emphasized. Although the theory under
consideration was very useful and adequate for many reactions in aqueous
solution, its many limitations soon became apparent. The theory includes
basic substanccs that arc not hydroxy compounds, docs not provide for
the amphotcrism exhibited by many oxides and salts, and limits the field
ofacid-basc reactions to aqueous solutions in spite of many known typical
neutralization reactions in non-aqucous solutions.
These objections led to more or less conflicting theories: the protonic
theory advanced by Bronstcd and Lowry in 1923 and the older solvent
system advanced by Franklin in 1905 and later extended. In terms o f the
Ф then popular protonic conccpt, a base is any substancc, molecule, or ion,
which accepts a proton.
Words and YVord-Combinations to Be Memorized
acidify, acidity, adequate, amphoteric, amphotcrism, conductance under
consideration, dye, electrolyte, extend, feel, of importance, incident, incidentally,
instead of, of interest, medium, objection, plant, provide, in question, role,
smooth, solvent, under study, in spite of, typical
Ex. 5. Give the Russian equivalents for the following:
lead to, an interesting theory, during the infancy, define, thus, neutralize
an acid, a plant dye, a smooth feeling, advance an idea, thereafter, an
experimental approach, place emphasis, instead of, electrolytic
conductance, propose a conccpt, a hydroxy compound, produce a salt,
incidentally, although, an adequate theory, become apparent, exhibit
amphotcrism, in spite of
Ex. 6. Give the English equivalents for the following:
ограничивать, (нс)воднын раствор, несмотря на, вести к, протон
ная теория, расширить систему, с точки зрения той теории, любое
169
вещество, принимать протон, после открытия кислорода, в основном,
состав вещества, теория кислотности, в начале XIX столетия, по этой
теории, роль растворителя, ионизирующая среда, рассматриваемая
идея, описать на основе поведения
Ex. 7. Fill in the blanks with articles where necessary.
1. In terms o f... protonic conccpt,... base is ... substancc which accepts
... proton. 2. The subject
of... acids and bases is one o f... most interesting
in ... chcmistry. 3. I n ... 18th ccntury Lavoisier advanced... idea that oxygen
was the acidifying principle of all acids. 4. Following... discovery of oxygen
... emphasis was placcd o n ... composition o f... substanccs. 5. Many typical
neutralization reactions occur in ... nonaqucous solutions.
Ex. 8. Give the synonyms for the following:
lead to, a series of, following (the discovery), advance an idea,
thereafter, a conccpt, producc, exhibit
Ex. 9. Give the antonyms for the following:
long, the most popular, before, in the early 19th ccntury, useful,
extend, older
Ex. 10. Translate the scntcnccs into Russian.
I. One of the most controversial problems in chemistry was that of acids
and bases. 2. The development o f the hydrogen theory of acidity and
Faraday’s studies of electrolytic conductance led to the water-ion theory.
3. The role of solvent as an ioinizing medium for acid-base reactions was
pointed out. 4. The property in question was very useful for many reactions
in aqueous solutions. 5. The theory was
important, but its many limitations
soon became apparent. 6. Analytical chcmistry detects, purifies, and answers
the questions “What?” and “How much?”. 7. A liquid solution, the occan,
covcrs three-fourths of the earth’s surfacc. 8. Any explosive substancc must
be handled with care. 9. Increase in pressure lessens the
volume of a gas;
increase in temperature increases the volume. 10. Calcium and silicon
carbides arc representatives of the direct union of carbon with metals and
non-metals. 11. The word “chcmical purity” is connected with the thought
of absencc of constituents other than the substancc in question. 12. The
atomic theory was John Dalton's great contribution to the world’s knowledge.
13. The most important chcmical property of oxygen is its acidity. 14. Pure
sulphuric acid is a colourlcss, oily liquid about twice as heavy as water.
IS. Atoms of the same element, with the same nuclear charge, but with
different weights, arc callcd isotopes of that clement. 16. Science must always
answer at least two questions — “What?” and “Why?”. 17. No branch of
scicncc is broader in its scope than chcmistry. 18. In a strict sense, no
substancc is entirely insoluble. 19. The then president o f the Russian
Academy of Sciences was М. V. Lomonosov. 20. One solution is said to be
more concentrated or more dilute than another. 21. Water is the most widely
170
distributed compound. 22. The properties of plant dyes is the problem under
consideration. 23. Another factor of great importance is the proper selection
o f reacting substanccs. 24. Let us consider the second condition. 25. Every
year a great number of new discoveries arc made in chcmistry. 26. Wc
consider it a step forward to develop the new technology of obtaning this
material. 27. Both ways are possible. 28. The
hypothesis under study may
prove to be right. 29. It is not always possible to predict the far-off results.
30. The data below must be taken into account in this consideration.
Ex. 11. Translate the scntcnccs into English without using a dictionary.
1. Рассматриваемая теория весьма противоречива. 2. В XVII сто
летии кислоты и основания описывали только на основе их поведе
ния. 3. Считалось, что основания — это вещества, способные нейт
рализовать кислоты и обладающие рядом других характерных
свойств. 4. После открытия кислорода большое внимание стали уде
лять составу веществ. 5. Развитие водородной теории кислотности и
изучение электролитической проводимости привело к созданию тео
рии Аррениуса. 6. Для кислотно-основных реакций очень важна роль
растворителя.
Ex. 12. Answer the following questions:
1. What substanccs were regarded as bases in the 17th century? 2. What
important discoveries led to the water-ion theory? 3. What is a base
according to Arrhenius? 4. What arc die objections to the Arrhenius theory?
5. What theory was proposed in 1923?
Достарыңызбен бөлісу:


title: Section П - Санкт-петербургского государственного университета высшее профессиональное образование т. А. Степанова, И. Ю. Ступина

text:
Example:
I Ex. 1. Make
1
Ex. 2. Respond to the following statements:
1. The classification of substanccs into acids and bases has greatly
changcd. 2. The theory of ionic dissociation has played a great role in the
development of chcmistry. 3. The problem of nomenclature is still very
important in chcmistry.
Ex. 3. Give detailed answers to the questions.
1. What arc the characteristic properties of acids? 2. What is the modern
definition of a base? 3. What was the role of the theory by Arrhenius in the
development o f acid-base classification? 4. What is dissociation?
Ex. 4. Discuss the following topics:
1. The Problems o f Classification in Chemistry.
2. The Evolution of the Theory o f Acids and Bases.
3. The Present Conccpt of Acids and Bases.
Lesson
26
ГРАММАТИКА: Герундий и герундиальный оборот в функции определе
ния. Причастие и причастный оборот в функции опре
деления. Инфинитив после причастия II и слов
likely,
sure,
certain.
Достарыңызбен бөлісу:


title: Section I - Санкт-петербургского государственного университета высшее профессиональное образование т. А. Степанова, И. Ю. Ступина

text:
Section I Ex. 1. Practise your reading.
Liquid solutions provide an extremely convenient means of bringing
together carefully measured amounts o f reagents and of allowing them to
icact in a controlled manner.
Ex. 2. State what parts of speech the following words belong to:
press, pressing, pressure, compress, compressible, incompressible,
compression
Ex. 3. Define the meanings of the word respect in the following sentences:
1.
Wc respect our supervisor very much. 2. In this respect the two
substanccs arc alike. 3. Everybody has great respect to our lecturer in
173


title: Scction  III - Санкт-петербургского государственного университета высшее профессиональное образование т. А. Степанова,...

text:
Scction III
— What is the subject of the next Iccture?
— Why should 1 know? (I’ve no idea.)
— Haven’t you been at the previous lecture?
up short dialogues according to the example.
general chcmistry. 4. Selenium resembles sulphur in many respects. 5. My
opinion is in no respect different from the author’s. 6. With respect to
their properties, halogens arc of particular interest.
Ex. 4. Analyse the following sentence:
The most important problem of chcmistry is that of explaining the
behaviour of substanccs.
Text 26 A
Liquids and Solutions
Solids and gases represent the extreme states o f behaviour of
molcculcs. The liquid state can be thought o f as an intermediate condition
in which some o f the properties found in cither solids or gases arc
displayed. Liquids, like gases arc isotropic and flow readily under applied
stress, but like solids, they arc dense, relatively incompressible, and have
properties that arc largely determined by the nature and strength of
intcrmolccular forces. With rcspect to molccular order, liquids arc
substanccs considered to be intermediate between solids and gases. The
fact that liquids arc isotropic tells us immediately that they do not have
the extended latticc structure and long-range order of solids. Yet, the
density o f a liquid is generally only 10% less than that of its solid phase;
this must mean that the molccules in a liquid arc packcd together with
some regularity, and do not exhibit the complete chaos associated with
molcculcs in the gas phase.
One of the most important properties o f liquids is their ability of acting
as solvents. In the first place, liquid solutions provide an extremely
convenient means of bringing together carefully measured amounts of
reagents and o f allowing them to react in a controlled manner. Sccond, the
nature of the reactions which proceed and the speed at which they occur
can be greatly influenced by the properties o f the liquid solvent medium.
Finally, the physical properties of solutions are interesting and important,
because they can be used to determine molccular weights of dissolved
substances and to study the nature and strength o f forces between solvent
and solute molcculcs.
One o f the most engaging and absorbing features of the study of
chcmistry is the attempt to explain the behaviour of bulk matter in terms
o f molccular properties. Therefore, it is important to outline a molccular
picture which will help us to understand and relate phenomena associated
with the liquid state.
Words and Word-Combinations to Be Memorized
ability, absorb, bulk, complete, convenient, display, engage, generally,
intermediate, intcrmolccular, lattice, a means, outline, reagent, range, with
respect to, solute, strength
174
I think of, display some properties, dense, intcrmolccular forces, with
respect to, immediately, the lattice structure, the long-range order, mean,
be packed together, provide a means of, carefully measured, procccd,
flnsUly, because, the behaviour o f bulk matter, outline a picture, be
associated with, the strength o f forces
Ex. 6. Give the English equivalents for the following:
поведение молекул, жидкое состояние, либо... либо..., главным
образом, порядок расположения молекул, занимать промежуточное
положение между, на 10% меньше (больше), плотность жидкости,
способность действовать в качестве растворителя, протекать с опре
деленной скоростью, оказывать большое влияние, физические свой
ства растворов, определить атомный вес, растворенное вещество,
растворитель, растворимое вещество
Ex. 7. Fill in the blanks with articles where ncccssary.
1
liquid state can be thought o f as intermediate condition between
... solids and gases. 2 .... properties of liquids arc determined by ... na
ture and strength o f ... intcrmolccular forces. 3— density o f ... liquid is
generally only 10% less than that o f ... solid. 4. Their ability of acting as
... solvents is one o f ... most important properties o f ... liquids. 5. It is
important to outline ... molccular picture o f ... liquid state.
Ex. 8. Give synonyms for the following:
think of, display, under stress, largely, immediately, little, allow,
influence, feature, explain
Ex. 9. Give antonyms for the following:
incompressible, extend, long-range, less, convenient, be influenced
by, most important
Ex. 10. Translate the sentences into Russian.
1. One should follow the proceeding reaction very carefully.
2. Selenium, an element belonging to the sulphur group, is as much non-
metal as metal. 3. Many factors mentioned determine the reaction rate.
4. There is a striking resemblance between some elements. 5. St.
Petersburg University has its own publishing house. 6. The boiling point
of water is accepted to be 100°C. 7. Some objections were found to the
Arrhenius theory long believed to be true. 8. The most striking thing
about hydrogen is its extreme lightness. 9. An acid is defined as a
compound or an ion capable o f liberating a proton. 10. Two or more
atoms having identical nuclear charges but different numbers o f Acutrons
are said to be isotopes. 11. Ores containing as little as 2 per cent or even
less of copper or nickel arc worth mining. 12. Bond formation involving
\ Ex. 5. Give the Russian equivalents for the following:
175
elements toward the middle o f the periodic tabic occurs by the proccss
of clcctron sharing. 13. There arc a number o f different procedures being
used in qualitative analysis. 14. The calculation o f hydrogen ion
concentration in a solution containing a weak clcctrolytc is a difficult
one for the average student first facing this problem. 15. Sulphur dioxide
is more than twicc as heavy as air and is one o f the most easily liquefied
gases known. 16. The term “heat” of combustion refers to the amount of
heat liberated per mole o f the substancc burned. 17. Many industrial
processes depend for their succcss upon the solubilities of the compounds
formed. 18. The system o f chcmical symbols now used was proposed by
the Swedish chcmist Berzelius in 1818.19. Fluorine, though for a long
time known to exist, was not isolated until 1886. 20. There has been,
sincc earliest times, an atomic hypothesis thought to be implied by the
diffusion and the compressibility of gases on the one hand and by the
symmetry of crystalline solids on the other. 21. The question o f the
composition of air long supposed to be one of the elements was solved
only in the 18th ccntury. 22. Dangerous bactcria in drinking water may
be killed by small amounts o f chlorinc. 23. An clement is represented by
certain letters for ease in writing. This symbol stands for one atom of the
element. 24. There arc numerous methods for demonstrating the spectra
o f many of the elements. 25. In qualitative analysis there is usually greater
difficulty in diagnosing the cations present than in recognizing the anions.
26. In English, wc have the practicc of naming chcmical elements in
Greek and Latin. 27. As a rule, there arc several ways o f preparing an
element. 28. Mercury has the property, unusual for a metal, o f being a
liquid at room temperature. 29. The phenomena likely to arise during
the experiment must also be taken into account. 30. The amount of the
pure metal ccrtain to be obtained for the ore can be calculated in the
following way.
Ex. 11. Translate the sentences into English without using a dictionary.
1. Жидкое состояние, которое, как обычно думают, является про
межуточным, проявляет некоторые свойства и твердых всщсств, и
газов. 2. Подобно твердым веществам, жидкости являются плотны
ми. 3. Плотность жидкости, как обычно считают, только на 10% мень
ше плотности твердого вещества. 4. Способность быть растворите
лем — одно из основных свойств любой жидкости. 5. Представить
себе молекулярное строение жидкости — одно из важнейших усло
вий понимания природы се свойств.
Ex. 12. Answer the following questions:
1. What arc the main states of matter? 2. What factors determine the
properties of liquids? 3. Is there any diffcrcncc in the density of solids,
liquids and gases? 4. Why arc liquids usually thought of as solvents? 5. How
can one understand the phenomena associated with the liquid state?
176
|


title:
Lesson  2
ГРАММ АТИ К А: Простое сказуемое в действительном залоге (Continuous,
Perfcct).
Section 1

text:
Ex. 3. Pay attention to the following way оГ word-building:
основа глагола +
-tion [Jn] —»
сушсствитслыюс
consideration, contribution, direction, prediction, calculation, foundation,
intensification
основа глагола +
-er (-
or) [»] —» существительное
teacher, researcher, founder, discoverer, writer, worker, explorer, observer,
learner, receiver, speaker, visitor
основа слова + -ic [lk] —»
прилагательное
periodic, characteristic,
specific, energetic, economic, scientific, historic
Ex. 4. Give the initial forms of the following words:
served, greatest, making, shows, placed, properties, researches, ideas,
hypotheses, theories, laid, closed, villages, areas, said, tried
Ex. 5. Define what parts of speech the italicized words belong to:
1
. The periodic system of the
elements was the greatest contribution
to chcmistry. 2. It was
really the work of a genius. 3. It
adds much to the
present knowledge. 4. The clement No. 10
1
bears the name of Mendeleyev.
5. The periodic system is the
basis of modem teaching on substanccs.
Text 2 A
The World’s Greatest Chemist
The periodic system of the chcmical elements by Mendeleyev has long
sincc served as the greatest history-making contribution to the study of
nature. As any work of genius it shows two characteristic features: it adds
more to the present knowledge, and it fruitfully develops along different
directions in future.
It allowed to predict in advance the existence and properties of yet
undiscovered elements. Many outstanding researchers owe to it, to a
considerable degree, the ideas of their experiments, calculations, hypotheses
and theories. Take, for example, the German Otto Hahn, who discovered
the fission of the uranium nucleus. Or the
American Glenn Scaborg who
led a group of researchers that obtained, in laboratory conditions, a number
of elements, including mcndclcvium, named in honour of Mendeleyev.
That element bears the name of the great Russian scientist not only bccausc
Mendeleyev laid the foundation of the modem science of atom, but also
bccausc he drew his colleagues’ special attention to uranium (No. 92),
which at the time had closed his periodic table. A long train o f
transuraniums followed the once “final” uranium.
“The Mendeleyev system has served for almost 100 years as a key to
discovering new elements,’’ Scaborg wrote in 1955. It has retained its key
capacity until now.
12
To commcmoratc Mendeleyev himself, the Soviet researchers named
many newly discovered things on the earth or in the outer space after him:
a crater on the “back” side of the Moon, an underwater ridge in the Arctic
Ocean and the mineral mcndclcycviic. Villages, streets and establishments
such as the Moscow Institute of Chemical Technology, the Tobolsk
Pedagogical Institute, the All-Russian Institute o f Meteorology, the
Museum of the St. Petersburg University building (where the scientist
lived), the All-Russian Chcmical Socicty, etc. have got Mendeleyev’s name.
Mendeleyev, the explorer of nature, has found real immortality in
his pasting heritage. The periodic system hasn’t crumbled with time; on
the contrary, its structure has expanded. At present it is the basis of
modem teaching on substanccs, the structure of matter, atoms and nuclear
energy.
“The greatest chemist of the world” — this is Mendeleyev’s fame
among modem chcmists. Yes, he, the founder of modem chemistry and, to
a large degree, of modem physics, considered physical chcmistry his main
subjcct, while he successfully dealt with problems in different areas, from
mathematics and astronomy to meteorology, from philosophy to economics,
from technology to art. “He has penetrated everywhere,” the great Russian
poet Alexander Blok once said.
Mendeleyev’s notes on “three services to the Motherland” arc quite
interesting. He places work as an explorer of nature at the first placc.
He devoted himself to it. He tried to make his experimental and theore
tical results serve socicty. He also devoted much of his effort to teaching,
to the spread o f knowledge. Finally, the third important task in
Mendeleyev’s life was to do his best for the economic and industrial
progress of Russia.
Mendeleyev’s dreams have come true. As long as seventy years ago
the British magazine
Nature (of February 24,1934) wrote that in Russia
scientists like Mendeleyev are valued and their works help to intensify the
development
of science, technology and industry.
Words and Word-Combinations to Be Memorized
almost, attention, basis, bear, calculation, characteristic, chcmical, chcmist,
chcmistry, contribution, develop, devote, direction, draw attention, element,
existence, feature, found, knowledge, lay the foundation, modem, nature,
outstanding, period, periodic, predict, present, at present, property, researcher,
revolution, scientist, special, structure, subject, substancc, system
Ex. 6. Give the Russian equivalents for the following:
the greatest chcmist, the periodic system of the elements, any work,
characteristic features, to predict in advance, undiscovered elements, an
outstanding researcher, lay the foundation of smth., modem science, special
attention, nuclear energy, deal with smth., devote oneself to, do one’s best,
chcmical socicty
13
изучение природы, свойства элементов, носить имя кого-л., вели*
кий русский химик, современная химия, обратить внимание на что-л.,
назвать чьим-л. именем, всероссийский институт, наоборот, в на
стоящее время, физическая химия, основной предмет, мечты осу
ществились
Ex. 8. Fill in the blanks with prepositions where ncccssary.
Достарыңызбен бөлісу:


title: Scction  II - Санкт-петербургского государственного университета высшее профессиональное образование т. А. Степанова, И. Ю. Ступина

text:
Analysis of the motion of Brownian particles shows that their average
kinetic energy is J/, kT. Sincc cach particlc is to be considered as one of
the molcculcs of the liquid wc can concludc that tlic average kinetic energy
of a molcculc in a liquid is also V, kT — exactly the same as the kinetic
energy of a gaseous molcculc at tlic same temperature.
Упр. 3. Передайте основное содержание текста в исскольких пред
ложениях.
Упр. 4. Какое слово в тексте означает «подвергаться воздействию»?
Упр. 5. Найдите в тексте ответы на следующие вопросы:
1.
Почему трудно проследить движение одной молекулы жидко
сти? 2. Как в общем можно охарактеризовать движение молекул жид
кости? 3. Как выглядит взаимодействие молекул в жидкости? 4. Как
определяется средняя кинетическая энергия молекул жидкости?
Упр. б. Закончите следующие предложения:
1.
The molecules in a liquid a rc ... 2. To analyse the motion o f a single
molcculc is difficult bccausc ... 3. Brown discovered ... 4. Brownian
motion is caused ... 5. The average kinetic energy o f a molcculc in a
liquid i s ...
Достарыңызбен бөлісу:


text:
Section III Ex. 1. Make up short dialogues according to the example.
Example: — What’s the matter? (What’s the trouble?)
— It is cold in this classroom.
— It can’t be helped. You’d better go to room 312.
Ex. 2. Respond to the following statements:
1. The molccular motion in a liquid is not easy to describe.
2. Molcculcs in a liquid arc arranged in a rather orderly manner. 3. The
properties o f the liquid solvent medium influence the speed o f reactions
occurring in this medium.
Ex. 3. Give detailed answers to the questions.
1. In what way arc liquids and gases alike? 2. In what way do liquids
resemble solids? 3. Why are the physical properties of solutions important?
4. What forces act between the molcculcs in a liquid?
Ex. 4. Discuss the following topics:
1. The Liquid State as an Intermediate State Between Solids and Gases.
2. Molccular Motion of Liquids.
3. Properties of Liquids.
178


title: Lesson  27 - Санкт-петербургского государственного университета высшее профессиональное образование т. А. Степанова, И. Ю. Ступина

text:
mixtures. A solution of soap in water has a cloudy appcaiancc due to particles
which consist of many soap molcculcs collected together. Such a substancc
has properties and composition which might be described as either
inhomogcncous or homogeneous depending on die experiment to be done.
Therefore, there is no sharp dividing line between mixtures and solutions.
The requirement that solutions have continuously variable composition
distinguishes them from most compounds. However, many solid materials
wc commonly think of as compounds actually show variable composition.
Cuprous sulphide and ferrous oxide arc examples of compounds which
might also be thought of as solutions. No matter how carefully wc made
our definitions of solution, mixture, and compound, wc must expect to
find certain substanccs not to be uniquely classified as one of these. There
is no reason to cxpcct nature to be cooperative and producc only substanccs
which are easily classified, and sincc this is the case, the most useful
definitions are often the shortest, rather than the most exhaustive.
Words and Word-Combinations to Be Memorized
actually, appcarancc, brief, briefly, this is the case, certain, classify, clearly,
continuously, depending on, distinct, examine, familiar, ferrous, for,
homogeneous, level, as long as, mechanical, no matter, precisely, requirement,
to set, uniform, variable
Ex. 5. Give the Russian equivalents for the following:
to give a definition, to tell clearly and briefly, in spite of tlic fact, it is
often true, the most common concepts, over certain limits, as long as, a
cloudy appcarancc, the experiment to be done, a sharp dividing line, no
matter how carefully, sincc this is the ease
Ex. 6. Give the English equivalents for the following:
отличаться от, свойства растворов, вещества, которые можно найти
в природе, точно определить,
гомогенное вещество, переменный со*
став, исследовать на молекулярном уровне, четко классифицировать,
в зависимости от эксперимента, нет оснований ожидать
Ex. 7. Fill in the blanks with articles where necessary.
1.
It is rather difficult to give ... definition o f ... solution.
2.... word
“homogeneous'* sets ... true solution from ... mechanical mixture.
3— ferrous oxide i s ... example o f ... compounds wc may consider as ...
solution. 4. ... most useful definitions arc often ... shortest. 5. At ...
molccular level... properties o f ... solutions are not examined well enough.
Ex. 8. Give synonyms for the following:
precisely, distinct, different, examine, however, due to, consist of, many,
do, material, commonly, actually, show, also, sincc
180
1.
Why is it difficult to give a definition of a solution? 2. Solutions arc
among the least known substanccs, aren't they? 3. What is usually
considered as the main property of solutions? 4. In what way can you
characterize a solution of soap in water? 5. Can one easily classify
substanccs to be found in nature? 6. What definitions arc the most useful?
Достарыңызбен бөлісу:


title: Scction II - Санкт-петербургского государственного университета высшее профессиональное образование т. А. Степанова, И. Ю. Ступина

text:
O f these, the first three are common, and the last three, callcd
solid
solutions, occur less frequently. Mercury dissolved in zinc, hydrogen gas
dissolved in palladium metal, and zinc dissolved in copper arc examples
o f solutions in which liquid, gas and solid, respectively, arc dissolved in
solid. Apart from their mechanical properties, solid solutions do not differ
greatly from the solutions of liquids.
Упр. 3. Передайте основное содержание текста в нескольких пред
ложениях.
Упр. 4. Какое слово в тексте означает «помимо, кроме»?
Упр. 5. Найдите в тексте ответы на следующие вопросы:
1. Какие параметры использовались для описания физического
состояния веществ? 2. Как определяется состав раствора? 3. Как опи
сываются составные части раствора? 4. Что говорится о свойствах
газовых смесей? 5. Какие типы растворов относят к твердым раство
рам? 6. Чем отличаются твердые растворы от жидких?
Упр. 6. Закончите следующие предложения:
1. Pressure, volume, temperature and certain other variables were used...
2. A solution of ethyl alcohol contains... 3. A solvent is... 4. A solute is...
5. The most common types of solutions arc... 6. Solid solutions occur...
Достарыңызбен бөлісу:


text:
Scction III Ex. 1. Make up short dialogues according to the example.
Example:
— I don’t like lectures on history.
— Why not?
— Prof. N speaks too quickly, I can’t always follow him.
Ex. 2. Respond to the following statements:
1. There is a property that allows to distinguish a true solution. 2. The
properties of solutions can be understood at the molccular level. 3. Both
the solvent and the solute determine the properties of a particular solution.
Ex. 3. Give detailed answers to the questions.
1. What is considered to be a true solvent? 2. Can you give any examples
of natural solvents? 3. What kinds of solutions do you know? 4. What is
the most familiar type of solutions?
Ex. 4. Discuss the following topics:
1. The Characteristic Properties of Solutions.
2. Similarity and Difference Between Various Types of Solutions.
3. The Laws Describing the Properties of Solutions.


title: THE ADVERBIAL MODIFIER - Санкт-петербургского государственного университета высшее профессиональное образование...

text:
Text 28 A
Interactions in Electrolyte Solutions
In a solution of an cicctrolytc, it is often ncccssary to have a detailed
knowledge of the spccics present. New ions or uncharged molcculcs
resulting from interactions in the solution may behave quite differently
from the constituent ions of the cicctrolytc. Some properties o f the
solutions will be profoundly affcctcd, and the chcmist, in order to
understand these phenomena, will require to know the nature of the
spccics present. There arc a number o f formidable difficulties in the
analysis of such systems and, during the past forty years or so, a great
deal of work has been done on the problem. The equilibrium properties
of cicctrolytc solutions and the way in which ion-pair and complex
formation can be dctcctcd and quantitatively studied arc of primary
importance. Although the application of new physical and chcmical
methods has produced significant contributions in this field, the
information obtained from measurements of a system at equilibrium is
to some extent limited, and in studying the phenomenon it is desirable to
know the relevant kinetic parameters. Without this understanding, it is
sometimes impossible to sketch the actual reaction mechanism by which
the system approaches equilibrium. In general, wc may regard the
elucidation of the structure of an cicctrolytc solution as a difficult problem
which requires as many independent lines of attack as possible.
A good deal of succcss in the study o f molcculcs in the gas phase
prompted chcmists to attempt to build up theories o f solutions in an
analogous way. The classical theories regarded the solvent as merely
providing spacc in which the solute particles moved and interactions
between the ions and the solvent molcculcs were neglected. This
0 assumption can be questioned on the basis of even the most elementary
electrostatic considerations.
As long ago as 1833, both Faraday and Danicll concluded that
electrolysis took placc through the transport of clcctricity by mobile charged
Достарыңызбен бөлісу:


title: particlcs or ions which were discharged at the clcctrodcs. These ions were

text:
Words and Word-Combi nations to Be Memorized
assumption, behave, conclude, considerable, a good deal of, a great deal
of, detect, discharge, clcctricity, to some extent, interest, interaction, kinetic,
merely, mobile, ncglcct, or so, parameter, primary, realize, result from, transport
Ex. 5. Give the Russian equivalents for the following:
a detailed knowledge, result from interactions, affect profoundly, during
forty years or so, the equilibrium
properties of solutions, produce a signi
ficant contribution, the relevant kinetic parameters, ncglcct some parame
ters, the energy comes from, be of considerable interest
Ex. 6. Give the English equivalents for the following:
взаимодействия ионов и молекул в растворе, влиять
на свойства,
чтобы понять эти явления, есть ряд трудностей, в
течение последних
сорока лет, изучать количественно, иметь первостепенное значение,
получать информацию, ограничивать до некоторой степени, желатель
но знать, приближаться к равновесию, посредством переноса, по
движная заряженная частица, разорвать связь в молекуле, вводить в
раствор, для того чтобы понять, «сводный раствор
Ex. 7. Fill in the blanks with articles where ncccssary.
1. Sometimes it is ncccssary to have ... detailed knowledge about...
composition o f ... solution under test. 2. It is desirable to know ... relevant
kinetic parameters. 3. To understand... structure o f ... electrolyte solution
i s ... difficult problem. 4. It was concluded th at... clcctrolysis
took place
through ... transport o f ... clcctricity by ... mobile charged particles.
5. Much o f ... work has been done in ... aqueous systems.
Ex. 8. Give synonyms for the following:
a number of, a great deal of, do, produce, significant, information,
obtain, study, actual, regard, analogous
Ex. 9. Give antonyms for the following:
present, new, uncharged, differently, with, difficult, many, move, more
Ex. 10. Translate the sentences into Russian.
1. It is often ncccssary to understand interactions in clcctrolytc
solutions. 2. Some properties of the solutions will be profoundly affected.
3. In studying the properties o f a solution, it is desirable to know its
composition. 4. Interactions between the ions and the solvent molcculcs
were sometimes neglected. 5. On returning, wc shall continue our
investigation. 6. Tomorrow you must finish it up. 7. In studying a foreign
language, one must leam a lot of foreign words by heart. 8. You arc not
allowed to work in the laboratory without learning the safety instruction.
186
9. In the proccss of oxidation, the oxygen may be supplied by the air.
10. Solids dissolve in liquids only to a limited extent. 11. Pure water
conducts the electric current hardly at all. 12. Existence of germanium
was predicted by D. 1. Mendeleyev in 1871.13. Crystalline salts generally
diflUse rapidly. 14. Due to crowding during formation or to erosion after
formation, crystals arc seldom perfect 15. The chcmical properties of ozone
are similar to those of oxygen except for its being more activc. 16. Silicon
resembles carbon in forming a scries of volatile hydrides. 17. In dealing
with crystals, one first encounters ions— atoms or groups of atoms carrying
electrical charges. 18. Nearly all mercuric compounds sublime on being
heated in the closed vessel. 19. Two elements may combine spontaneously
upon being mixed or under special conditions. 20. A catalyst is defined as
a substancc that will change the rate of a chcmical reaction without itself
being changed. 21. Carbon burns in oxygen on strong heating. 22. In
studying chcmistry, it is ncccssary to consider the nature of all kinds of
matter. 23. By changing the temperature of the reacting substanccs or by
changing the concentration (mass, per unit volume), the inherent tendency
to react may be incrcscd or decreased. 24. Water, a compound of hydrogen
and oxygen, is widely distributed over the earth. 25. Natural radioactivity
was discovered by the French physicist Henri Bccqucrcl (1851-1908) in
1896 just shortly after W. K. Roentgen’s discovery of X-rays in 1895.
26. Different real gases have slightly different molar volumes. 27. The
forces acting between atoms in a molcculc are very strong, and those acting
between molcculcs arc weak. 28. The heat capacity of a substancc at, say,
25°C is not necessarily the same as that measured at another temperature.
29. Covalency links arc those commonly met with in carbon compounds.
30. Finely divided barium sulphate has a great tendency to absorb other
ions from solutions.
Ex. 11. Translate the scntenccs into English without using a dictionary.
1. Для
анализа раствора электролита необходимо знать, какие
частицы находятся в нем. 2. Ионы электролита и новые ионы, полу
чающиеся в результате взаимодействий в растворе, ведут себя по-
разному. 3. Большое внимание уделялось изучению растворов за пос
леднее время. 4. Еще в 1833 году был сделан вывод, что электролиз
происходит посредством переноса электричества подвижными заря
женными частицами. 5. Как водные, так и неводные растворы пред
ставляют интерес для исследователей.
Ex. 12. Answer the following questions:
1.
Why is it ncccssary to know the spccics present in solution? 2. What
do the properties of cicctrolytc solutions depend on? 3. What knowledge
helped chcmists to build up theories of solutions? 4. What fundamental
conclusion made it possible to investigate cicctrolytc solutions
successfully? 5. What processes take placc in electrolyte solutions?


text:
dissociated into ions, and observed deviations from this ideal behaviour
arc then ascribed to electrical interactions between the ions.
Упр. 3. Передайте основное содержание текста в нескольких пред
ложениях.
Упр. 4. Какие слова в тексте означают «закон действия масс»?
Упр. 5. Найдите в тексте ответы на следующие вопросы:
1. Каковы основные положения теории ионизации? 2. Чем, по
мнению Аррениуса, объяснялось уменьшение проводимости при уве
личении концентрации? 3. Какое допущение послужило основанием
для теории Брснсгсда? 4. Какая теория наиболее успешно объясняла
поведение разбавленных растворов? 5. Как объясняется поведение
ионов в растворе на основе теории Дебая и Хюкксля?
Упр. б. Закончите следующие предложения:
1. The original postulate suggested by Arrhenius is invalid bccausc...
2. Bronstcd made considerable advances in... 3. The first statistical
theory o f cicctrolytc solutions was... 4. According to the theory
developed by Debye and Hiickcl, an ion atmosphere surrounding each
ion in solution is due to... 5. Using the theory by Debye and Hiickcl
one can calculate...
Достарыңызбен бөлісу:


text:
Section III Ex. 1. Make up short dialogues according to the example.
Example:
— I don’t quite catch the difference between these theories.
— Look here, it’s very simple. The main point is the difference
in the behaviour of ions.
— Oh, now I see. Thanks a lot.
Ex. 2. Respond to the following statements:
1. A great deal of work has been done on the problem of interactions
in cicctrolytc solutions. 2. Theories of solutions are in some respects similar
to theories of gases. 3. The problem of clcctrolysis has interested chcmists
for almost two ccnturics.
Ex. 3. Give detailed answers to the questions.
1.
What do the properties of cicctrolytc solutions depend on? 2. Whose
contribution to the development of the theory of electrolyte solutions was
of considerable importance? 3. What fundamental ideas have been
developed at the department o f the theory of solutions of the University of
St. Petersburg?
189
Ex. 4. Discuss the following topics:
1. The Behaviour of Electrolyte Solutions.
2. The Development of Ideas conccming Electrolyte Solutions.
3. Generally Acccptcd Principles Conccming Electrolyte Solutions.


Lesson 29
ГРАММАТИКА: Причастие и причастный оборот в функции обстоятель
ства. Независимый причастный оборот.
Section I
Ex. 1. Practise your reading.
The temperature remaining constant, the fraction of liquid molcculcs
with enough kinetic energy to evaporate remains the same, and evaporation
continues.
Ex. 2. State what parts of speech the following words belong to:
vapour, vaporous, vaporablc, vaporization, vaporizability, vaporize,
evaporate, evaporation, evaporative, evaporator
Ex. 3. Define the meanings of the word until in the following sentences:
1. Continue heating until the solution evaporates completely. 2. Don’t
do anything until I comc. 3. Day after day he works until night.
4. Evaporation continues until no liquid is left. 5. It was not until the atomic
theory was established that chcmisuy became a nature science founded on
scicntific principles. 6. It was not until March 1869 that the paper on the
periodic table was presented at the meeting of the Russian chcmical society.
7. Let us wait for him until 9 o’clock and if he doesn’t comc, wc shall go
away. 8. There is no suitable technique until now.
Ex. 4. Analyse the following sentence:
The temperature remaining constant, evaporation continues at a
constant rate.
Text 29 A
Liquid-Vapour Equilibrium
A liquid o f relatively low boiling temperature, when placed in a
container open to the atmosphere, will eventually evaporate entirely.
Remembering that molcculcs in the liquid arc “bound" by attractive forces
to their neighbours, wc might ask why some arc able to overcome these
forces and leave the liquid spontaneously. The answer lies in a consideration
1 О Л
o f the possible magnitudes of molccular kinetic energies, for these, as wc
have already mentioned, range from very low to very high values, and arc
distributed according to the Maxwcll-Boltzmann law. Therefore, even if
the average potential energy which binds the molcculcs to the liquid is
substantial, there arc always some molcculcs which have enough kinetic
energy to overcome the binding forces and enter the vapour. According to
the Maxwcll-Boltzmann law, the fraction of the molcculcs which have kinetic
energies greater than some minimum value e, the value required for the
molcculcs to leave the liquid, is proportional to the Boltzmann factor, e*t/ir.
Therefore, the temperature remaining constant, the fraction of liquid
molcculcs with enough kinctic energy to evaporate remains the same, and
evaporation continues. The vessel being open to the atmosphere, vapour
molcculcs arc swept away, and evaporation continues until no liquid is left.
Now, let us analyse what happens when a liquid is placcd in a closed
evacuated container. Immediately, the liquid starts to evaporate at a rate
which is primarily determined by the fraction o f molcculcs which have
enough kinctic energy to overcome attractive forces and leave the surfacc.
Initially, the rate of condensation is zero, there being no molcculcs in the
vapour. As long as the temperature stays constant, evaporation continues
at a constant rate, and the number o f molcculcs in the vapour phase
increases. Consequently, the rate of condensation starts to increase, for as
the pressure of the vapour grows, the number of gas molecules which
collidc with and reenter tlic liquid surfacc also increases.
The time dcpcndcncc of the evaporation and condensation rates is worth
considering. While growing, the condensation rate eventually bccomcs
equal to the rate of evaporation. At this time, the number of molcculcs
which enter and which leave the vapour per unit time is the same, and,
consequently, the pressure of the vapour stops increasing and remains
constant. If the system is left undisturbed at a fixed temperature, evaporation
and condensation continue at equal rates, and the pressure of the vapour
remains unchanged. This, then, is a situation of equilibrium between the
two phases. Note particularly that at equilibrium, evaporation and
condensation do not stop, but that the constancy of the equilibrium vapour
pressure is a conscqucncc of these opposing processes proceeding at equal
rates. Thus wc say that phase equilibrium is dynamic in nature.
Words and Word-Combinations to Be Memorized
analyse, attractive, bind, constant, dependence, initial, magnitude, note,
primarily, proportional, situation, spontaneous, substantial, it was not until...
that, not until, vessel, zero
Ex. 5. Give the Russian equivalents Гог the following:
evaporate, entirely, overcome the forces, leave the liquid, the magnitude
of the energy, range from... to, substantial, overcome the binding forces,
be proportional to, remain the same, start immediately, the dependence is
191
worth considering, bccomc equal to, per unit time, consequently, at a fixed
temperature, remain unchanged, opposing processes
Ex. 6. Give the English equivalents for the following:
относительно низкая температура, поместить в сосуд, преодолеть
силы притяжения, самопроизвольно, средняя потенциальная энергия,
открытый сосуд, давайте проанализируем, начинать испаряться, пер
воначально, с постоянной скоростью, давление пара растет, положе
ние равновесия
Ex. 7. Fill in the blanks with articles where ncccssary.
1. Let us analyse what happens when ... liquid is placed in ... closed
evacuated container. 2. As long as ... temperature remains constant, ...
evaporation continues a t ... constant rate. 3. As ... pressure o f... vapour
grows,... number o f ... gas molcculcs returning t o ... liquid also increases.
4
time dependence o f... evaporation and condensation rates should be
considered. S. At equilibrium,... evaporation and condensation do not stop.
Ex. 8. Give synonyms for the following:
magnitude, mention, substantial, fraction, remain, place, primarily,
initially, increase, equal
Ex. 9. Give antonyms for the following:
low, open, leave, minimum, the same, continue, container, immediately,
start, also, consequently
Ex. 10. Translate the scntcnccs into Russian.
1.
Heating the substancc, one must be very attentive. 2. While moving,
molcculcs collide with each other. 3. When at the laboratory, one must
observe safety rules. 4. Our lecturer being ill, wc had no Iccture yesterday.
5. Our assumption confirmed, wc could continue the experiment. 6. The
Iccturc being over, wc shall have a long break for dinner. 7. If present in
air in larger amounts than 1 in 20,000 by volume, ozone is irritant and
poisonous. 8. Practically, all acids when pure arc polar molccular structures.
9. Having made a number of experiments with calcium and sulphuric acid
at the temperature of 40°C, the Russian engineer Petrov was the first to
put forward the problem of chcmical activation. 10. One must be very
carcful when heating potassium chlorate. 11. Any clement when combining
with oxygen forms an oxide. 12. While dealing with chemicals in a
laboratory, one can’t do without such apparatus as funnels, beakers and so
on. 13. Once discovered, the periodic system of the elements received
much scicntific attention. 14. Unless otherwise stated, volumes of gases
always refer to standard conditions of temperature and pressure. 15. No
substancc can be considered chemically dry unless specially treated.
16. Large pieces of sodium may produce dangerous explosions if plaecd
192
0n water. 17. Sodium hydroxide is prepared industrially by two general
jpcthods, the oldest being the reaction of sodium carbonate and calcium
hydroxide. 18. Hydrogen peroxide being added to an acidified solution o f
potassium permanganate, bubbles of gas arc evolved, the gas evolved being
oxygen. 19. The formula of a compound being known, wc can calculate
its molccular weight. 20. The liquid state being intermediate between the
solid and gaseous state, tlic properties of the liquids show similarities to
those of both solids and gases. 21. Cobalt and nickel arc much more resistant
to atmospheric oxidation than iron, with nickel being especially resistant.
22. Considered from this point of view, the reaction mcchanism seems to
depend only on the following three factors. 23. Having analysed the data,
the author found that they were in agreement with the theory. 24. Having
been heated to I00°C, water began to boil. 25. Having finished the
experiment, we must proccss the data. 26. Exccpt where otherwise stated,
the measurements were taken at room temperature. 27. Other things being
equal, pressure grows proportionately to the temperature. 28. Having
discovered the law of periodicity of the chcmical elements, Mendeleyev
made his greatest contribution to the development o f chcmistry.
29. Studying the properties of any substancc, the chcmist has to perform a
number of experiments. 30. Lavoisier (1745-1794), believing oxygen to
be a constituent of all acids, gave it the name oxygen (Greek: acid-former).
Ex. 11. Translate the scntcnccs into English without using a dictionary.
1. Если жидкость с низкой температурой кипения находится в
открытом сосуде, она в конце концов полностью испарится. 2. Моле
кулы жидкости связаны с соседними молекулами силами притяже
ния. 3. Некоторые молекулы обладают достаточной кинетической
энергией для того, чтобы преодолеть силы связывания и перейти в
пар. 4. При прочих равных условиях, пока температура остается по
стоянной, испарение продолжается с постоянной скоростью. 5. Если
жидкость находится в закрытом сосуде, необходимо рассмотреть про
цесс конденсации.
Ex. 12. Answer the following questions:
1. What happens with a liquid if it is placcd in an open container?
2. What forccs act between the molcculcs in a liquid? 3. Under what
conditions can some molcculcs leave the liquid? 4. What happens if a
liquid is placcd in a closed evacuated container? 5. What docs the rate of
condensation depend upon? 6. What situation is callcd equilibrium
between the liquid and vapour phases?
Достарыңызбен бөлісу: |


title: Санкт-петербургского государственного университета высшее профессиональное образование т. А. Степанова, И. Ю. Ступина - бет 11

text:
dclcycv published his periodic system in 1869. 12. Mendeleyev’s law
helped the American Glenn Scaborg who led a group of researchers to
obtain a number of elements, including mcndclcvium, in laboratory
conditions. 13. The laboratory led by Academician Georg Flyorov has
been the cradle of many transuraniums. 14. Mendeleyev had been active
in founding the Russian Chcmical Socicty, which held its First meeting on
November
6
, 1868. IS. The predictions did not seem surprising; the
succcssivc discoveries of gallium (1874), scandium (1879), and germanium
(188S) followed. 16. It is a remarkable fact that Mendeleyev actually spent
only a few years in developing the periodic table, and then went on to
other work.
Ex. 11. Translate the sentences into English.
1. Периодическая система элементов Д. И. Менделеева стала из*
всстна в 1869 году. 2. Она позволила заранее предсказать существо
вание и свойства нескольких элементов. 3. Менделевии, один из
трансурановых элементов, носит имя ученого, который привлек вни
мание коллег к урану. 4. Д. И. Менделеев— основатель современной
химии и, в значительной степени, современной физики. 5. Он посвя
тил себя изучению природы.
6
. Всю свою жизнь Д. И. Менделеев
делал все возможное для прогресса России в области науки и эконо
мики. 7. Его закон заложил основу для современной науки об атоме.
8
. В настоящее время периодическая таблица сильно отличается от
периодической таблицы 1869 года. 9. Каждый период таблицы Мен
делеева содержит определенное число элементов. 10. Например, в
первом периоде — только два элемента. 11. До Менделеева были
попытки расставить элементы в некотором порядке.
Ex. 12. Make up questions to the italicized parts of the sentences.
I.
Mendeleyev is one of the greatest
chemists (2). 2. He published
his
periodic
system in 1869 (3). 3. Mendeleyev
predicted some
properties of
undiscovered elements (
2
).
Ex. 13. Answer the following questions:
1
. Why is the periodic system by Mendeleyev valued so much? 2. Why
docs the element No. 101 bear Mendeleyev’s name? 3. Has the periodic
tabic changed with time? In what way has it changed? 4. What information
is it possible to get from the periodic table o f elements? 5. Was
D. I. Mendeleyev a man of wide interests? Prove it.
6
. What docs the
periodic law state?
Достарыңызбен бөлісу:


text:
Scction II
Упр. 1. Назовите значения следующих интернациональных слов:
normal, initiation, guarantee, final, introduce, agent, porous, ccramic
Упр. 2. Проверьте, помните ли вы значения следующих слов; если
нет, обратитесь к словарю:
sensitive, raise, bubble, exert, hence, rcach, violence, exceed, avoid, evolve
Text 29 В
Прочтите текст про себя (контрольное время чтения— 3,5 минуты).
Temperature Dependence of Vapour Equilibrium
Experimental measurements show that the equilibrium vapour
pressure o f a liquid increases as the temperature increases. In the
temperature range in which the vapour pressure is small, it is relatively
insensitive to the temperature, but the vapour pressure grows at an
increasing rate as the temperature is raised. The temperature at which
the equilibrium vapour pressure becomes equal to 1 atm is callcd the
normal boiling temperature, or the boiling point. In the boiling process,
bubbles of vapour form throughout the bulk of the liquid. In other words,
evaporation occurs anywhere in the liquid, not just at the upper surface.
The reason that this occurs only when the vapour pressure equals the
atmospheric pressure is easy to understand. In order for a bubble to form
and grow the pressure o f the vapour inside the bubble must be at least
equal to the pressure exerted on it by the liquid. This, in tum, is equal to
the pressure of the atmosphere plus the very small pressure due to the
weight o f the liquid above the bubble. Therefore, bubble formation and
boiling occur only when the vapour pressure o f the liquid is equal to the
pressure o f the atmosphere.
The initiation of a bubble in the bulk of a pure liquid is a vciy difficult
proccss, since it requires that many molcculcs with kinctic energies greater
than that required for vaporization must be elose to one another. Hcncc,
the fact that the liquid rcachcs the boiling temperature is no guarantee that
boiling will occur. If it docs not, continued addition of heat will causc the
liquid to bccomc superheated, that is, to rcach a temperature greater than
its boiling point. When finally occurring in a superheated liquid, the bubble
formation proceeds with almost explosive violence, because the vapour
pressure in any bubble formed greatly exceeds atmospheric pressure, the
bubbles tending to expand rapidly. Such violent boiling can be avoided
introducing agents which initiate bubbles in the liquid as soon as the boiling
temperature is rcachcd. Porous picccs of ceramic material which evolve
small bubbles of air into which evaporation can occur serve very well in
this application.
Упр. 3. Перелайте основное содержание текста в нескольких пред
ложениях.
Упр. 4. Какие слова в тексте означают «в свою очередь»?
Упр. 5. Найдите в тексте ответы на следующие вопросы:
1. In what way docs the vapour pressure change at equilibrium?
2. What is the normal boiling temperature? 3. Under what conditions
194
does the initiation of a bubble in the bulk of a pure liquid occur? 4. When
does the liquid bccomc superheated? 5. What arc porous picccs of ccramic
material used for?
Упр. 6. Закончите следующие предложения:
1.
The vapour pressure grows at an increasing rate... 2. The boiling
point of a liquid is... 3. Bubble formation and boiling occur only when...
4. The fact that the liquid reaches the boiling temperature is no guarantee
that... 5. Violent boiling can be avoided...
Достарыңызбен бөлісу: |


text:
Section III Ex. 1. Make up short dialogues according to the example.
Example:
— What kind of equipment do students learn to use in your lab?
— First of all, we learn to handle test-tubes, beakers, funnels,
burners and so on.
— It’s quite natural. You can’t do without all these things if
you area chemist.
Ex. 2. Respond to the following statements:
1. The processes of evaporation in an open container and in a closed
one arc not the same. 2. It is interesting to consider the time dependence of
the evaporation and condensation rates, isn’t it? 3. One can easily describe
what happens in a liquid when it begins boiling.
Ex. 3. Give detailed answers to the questions.
1. In what way docs vaporization procccd? 2. What is liquid-vapour
equilibrium? 3. How docs temperature influence the vapour pressure?
Ex. 4. Discuss the following topics:
1. The Vaporization Proccss.
2. The Phase Equilibrium.
3. Factors Influencing the Vapour Pressure.


title:
Lesson  30
ГРАММАТИКА: Инфишгтв и инфинитивный оборот в функции обстоя
тельства. Придаточные обстоятельственные предложения.
Section I

text:
The liquids (hai form an ideal solution arc always misciblc in any
proportions and, thus, have infinite solubility in cach other. The reason
for this is easy to see if wc rccall two facts. First, limited solubility and
a saturated solution result only when a solute and its solution reach
equilibrium. Second, the equilibrium state is a compromise between a
natural tcndcncy toward minimum energy and maximum molccular chaos.
Now, the mixing o f two ideal liquids is always accompanied by an
increase in entropy or molccular chaos, bccausc in the solution, the solute
molcculcs arc spread randomly throughout the solvent, rather than being
nearly closest packed as they arc in the pure solute. That is, even if wc
could locate one solute molcculc in solution, wc could not predict what
the identity of its nearest neighbours was, as wc could, if the molcculc
were in the pure solute phase. Consequently, the solution has a higher
entropy than the pure solvent and solute, and the tcndcncy toward
maximum molccular chaos favours the mixing o f the two liquids.
Moreover, the fact that there is no energy changc in the mixing proccss
means that the tcndcncy toward minimum energy docs not restrict the
solution proccss. Consequently, the two liquid components o f an ideal
solution can mix in any proportion.
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title: Санкт-петербургского государственного университета высшее профессиональное образование т. А. Степанова, И. Ю. Ступина - бет 123

text:
/
Words and Word-Combinations to Be Memorized
as is the case with, as the case may be, in case, in which case, it is far from
the ease, it is not the case with, such is the ease, a chemical, contact, emphasize,
excess, experience, be a matter of common experience, favour, ideal, identity,
maintain, maximum, natural, purify, result, saturate, saturated, solubility, spread,
themselves, toward(s), a variety of
Ex. 5. Give the Russian equivalents for the following:
mix in any proportions, the capacity to dissolve a solute, placc in contact
with, the solubility in a particular solvent, purify chemicals, be a controlling
factor, a variety of phenomena, be controlled by the nature of the solvent
and solute, be misciblc in any proportions, be spread randomly throughout
the solvent, be close packcd, moreover, restrict the proccss, emphasize the
importance
Ex. 6. Give the English equivalents for the following:
общеизвестно по опыту, что.. ограниченная способность, избы
ток растворимого вещества, быть в равновесии, в насыщенном ра
створе при данной температуре и давлении, другими словами, значе
ние концепции растворимости для химии, во множестве природных
явлений, ограничиться случаем, идеальный раствор, достигать рав
новесия, сопровождаться увеличением температуры, а не..., даже
если, нет изменения энергии
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1. Substanccs like ... water and ... ethyl alcohol can be mixed in any
proportions. 2. ... capacity o f ... solvent to dissolve ... given solute is
often limited. 3 .... solubility o f ... substancc in ... particular solvent at
... given temperature is its concentration in ... saturated solution. 4. It is
difficult to overemphasize... importance o f ... conccpt o f ... solubility to
... chcmistry. 5. Wc shall first analyse... case o f... ideal solution.
Ex. 8. Give synonyms for the following:
capacity, limit, place, principally, be accompanied by, because, toward,
consequently
Ex. 9. Give antonyms for the following:
constant, saturated, at first, always, easy, decrease, near, minimum,
seldom, limited
Ex. 10. Translate the scntcnccs into Russian.
1. The capacity of a solvent to dissolve a given solute is often limited
though there arc many pairs of substanccs which can be mixed in any
proportions. 2. In order to control our environment, the first purpose of
science must be to study and understand it. 3. To answer the question
“What arc the uses of sulphuric acid?” fully, one would need to write a
book. 4. The alkali metals arc usually stored in oil so as to cxcludc air.
5. In order for two molcculcs to react with each other, they must, first of
all, be in the prcsencc o f each other. 6. For hydrogen to be obtained from
water, electrolysis may be used. 7. Sodium is a white metal soft enough to
be easily cut with a knife and light enough to float on water. 8. The minerals
in which aluminium occurs, arc too numerous to recite. 9. The vapour
pressure of many pure liquids or solids is very low, in fact, so low as to be
immeasurable by direct means. 10. The catalytic substancc can be recovered
unchanged after the reaction is completed. 11. As the temperature is raised,
the rate of evaporation increases. 12. Oncc the validity of a hypothesis has
been tested by all possible experiments and is found to be in harmony
with all the facts, it assumes the status of a theory. 13. Whenever a chcmical
reaction occurs, an energy changc takes place. 14. Liquid bromine should
be kept in well-stopped bottles, as this clement is poisonous. 15. The
discovery of silicon was an important event in chcmistiy, for the properties
o f the clement were found to be very close to those predicted by
D. I. Mendeleyev on the basis of his periodic law. 16. Where the current
enters or leaves the liquid, there are evidences o f chcmical action having
taken placc. 17. If sulphur trioxidc is thrown into water, it will dissolve
with the evolution of much heat. 18. If there were no order in the way in
which atoms of different elements combine to form the molcculcs and
crystals of compounds, it would be ncccssary for us to memorize one by
one the formulas of thousands of substanccs. 19. If wc had chosen the
second oxide, the valcncc of sulphur and, therefore, its equivalent weight
Ex. 7. Fill in (he blanks with articles where ncccssary.
198
would have been different. 20. With a few exceptions the molten metals
arc completely soluble in one another, so that it is possible to make solutions
of all concentrations. 21. True salts are always ionic, whether they arc in
solution or in their crystalline forms. 22. Fluorine and hydrogen combinc
violently even in the dark, provided a trace o f moisture is present.
23. Strange as it may seem, the reaction may procccd both ways.
24. Important as the problem of solubility may be, wc shall not consider it
now. 25. Let us consider any factors lest anything may be omitted.
26. Unless the clcctron microscopc had been used, it would not have been
possible to obtain these results. 27. Were the parameters maintained, the
reaction would go to completion. 28. Physics and chcmistry arc so closely
related that textbooks of these two subjects contain much in common.
29. Many oxides arc found to combinc with acids to form salts and water.
30. Carbon monoxide cannot properly be described as cither a basic or an
acidic oxide, inasmuch as it docs not react with water.
Ex. 11. Translate the sentences into English without using a dictionary.
1. Различные вещества обладают различно» способностью раство
ряться в данном растворителе. 2. Растворимость вещества — это его
концентрация, характерная для состояния равновесия между раство
римым веществом н раствором. 3. Понятие растворимости представ
ляет собой основу для многочисленных лабораторных и промышлен
ных процессов. 4. Растворимость зависит как от природы самих
растворителя и растворяемого вещества, так и от условий процесса.
5. Два жидких компонента идеального раствора могут смешиваться
в любой пропорции.
Ex. 12. Answer the following questions:
1. In what way can the capacity of a solvent to dissolve a given solute
be characterized? 2. What state is regarded as equilibrium between the
a solute and solution? 3. What is usually callcd the solubility of a substancc
in a particular solvent? 4. What is the importance o f the conccpt o f
solubility? 5. What is an ideal solution?
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text:
Text 30 В
Прочтите текст про себя (контрольное время чтения — 3,5 минуты).
Nonideal Solutions
Consider a solid substancc dissolving in a liquid solvent. The solid is
such that when melted, it is converted to a liquid that, in turn, can form an
ideal solution with the solvent. The dissolution of the solid can be pictured
as occurring in two hypothetical stages:
solid solute —» liquid solute —» solute in solution.
The second o f these steps docs not
involve any energy change, for the
solution formed is ideal. In contrast, the first step docs involve the
absorption of energy in the amount
per mole of solute. Consequently,
while the tendency toward maximum entropy favours the dissolution of
the solid, the tendency toward minimum energy favours the solid remaining
undissolvcd. Therefore, the solubility of the solid is limited, and a saturated
solution which represents the best compromise between maximizing
entropy and minimizing energy is formed. Since дНГд, is related to the
strength of attractive forces between solute molcculcs, wc can dcducc that
the magnitudes o f these same forces determine the solubility
of the solid
in ideal solutions.
By using some care, wc can extend our aigumcnts to nonidcal solutions.
Two liquids which mix with the evolution o f heat will be infinitely soluble
in each other, for both energy and entropy ciTccts favour their mixing.
Two liquids which mix with the absorption o f heat may have limited
solubility in each other, for if the mixing proccss is energetically
unfavourable, the tcndcncy toward maximum molccular chaos may or may
not be sufficient to allow the liquids to mix in all proportions. Likewise,
the solubility o f a solid is likely to be small if it enters the solution only
with considerable absorption of heat. On the other hand, if the dissolution
o f the solid is accompanied by evolution o f heat, the solubility of the solid
may be quite high. Even with these generalizations it is difficult to predict
or even rationalize qualitatively the solubilities of substanccs that form
markedly nonidcal solutions, for the energy and entropy changes that
accompany the mixing o f strongly irrcacting molcculcs arc subtle and
difficult to anticipate.
Упр. 3. Передайте основное содержание текста в нескольких пред
ложениях.
Упр. 4. Какое слово в тексте означает «представить себе»?
Упр. 5. Найдите в тексте ответы на следующие вопросы:
I. What hypothetical steps can be pictured when a melted solid is
dissolved? 2. At what stage docs the energy change take place? 3. Why is
the solubility of the solid limited? 4. What two liquids will be infinitely
soluble in each other? 5. When will the solubility of the solid be high?
200
Упр. 6. Закончите следующие предложения:
1.
The magnitudes of the attractive forces determine... 2. Two liquids
will be infinitely soluble in cach other if they mix with... 3. Two liquids
mixing with the absorption of heat may have... 4. It is difficult to predict...
5. If the dissolution of the solid is accompanied by evolution of heat...
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title: Section  III - Санкт-петербургского государственного университета высшее профессиональное образование т. А. Степанова,...

text:
Section III Ex. 1. Make up short dialogues according to the example.
Example: — Why didn’t you come to the seminar yesterday?
— Bccausc I’ve missed Dr. N’s lecture.
— I see. Having missed the lecture, you couldn’t take
part in the discussion.
Ex. 2. Respond to the following statements:
I. The proccss of dissolving a solid in a liquid is different from the
proccss of dissolving a liquid in a liquid. 2. Solubility depends on a number
of factors. 3. One can easily predict tlic solubility of a particular solute in
a given solvent.
Ex. 3. Give detailed answers to the questions.
1. What is solubility? 2. What docs the solubility of a substancc depend
on? 3. What is the difference between an ideal and nonidcal solution?
Ex. 4. Discuss the following topics:
1. Solubility of Liquids.
2. Solubility of Solids.
3. Factors Influencing Solubility.


title:
PARENTHESES
Lesson  31 - Санкт-петербургского государственного университета высшее профессиональное образование...

text:
PARENTHESES
Lesson 31
ГРАММАТИКА: Вводные члены
предложения.
Инфинитив
н
причастие
в функции вводного члена предложения.
Section I
Ex. 1. Practise your reading.
The terms “oxidation" and “reduction” now arc applied to reactions in
which neither oxygen nor hydrogen arc involved.
Ex. 2. State what parts of speech the following words belong to:
oxide, oxidablc, oxidability, oxidant, oxidate, oxidation, oxidative,
oxidic, oxidize, oxidizablc, oxidizability, oxidizer, oxygen, oxygenate,
oxygenize, hydroxide, dioxide
Ex. 3. Define the meanings of the word put in the following sentences:
1. Please,put this book on the shelf. 2. Put down the apparatus, never hold
it in your hands during operation! 3. The idea was put forward that ozone
is essential in protecting life on the Earth. 4. To put the instrument into
operation press the red button. S. It seems to me that this is a utopian idea
and it can never be put into practicc. 6. To put it in another way, these two
terms mean the same. 7. Never put ofT till tomorrow what you can do today.
Ex. 4. Analyse the following sentence:
Strictly speaking, wc cannot say that wc know everything about oxidation.
Text 31 A
Oxidation and Reduction
Generally speaking, the simple meanings o f these terms arc that
oxidation is the addition of oxygen to a substancc and reduction is the
202
icmoval of oxygen. Needless to say, hydrogen seems to be the chcmical
opposite of oxygen (the two elements combine readily, and arc evolved at
opposite clcctrodcs during clcctrolysis). Removal of hydrogen is, therefore,
similar to the addition of oxygen, and addition of hydrogen is similar to
the removal of oxygen. Fuller meanings of the two terms arc therefore:
Oxidation is the addition of oxygen to, or removal of hydrogen from, a
substancc. Reduction is the removal o f oxygen from, or addition o f
hydrogen to, a substancc.
2S02 + 0 2 2=5 2SOj
(oxidation of S 02; addition of oxygen)
PbO + Hj — Pb + HjO
(reduction of PbO; removal of oxygen)
Cl2 + H: — 2HC1
(reduction of Cl2; addition of hydrogen)
H2S + Cl: ~ * Si + 2HCI
(oxidation of HjS; removal of hydrogen)
The terms now arc applied to reactions in which neither oxygen nor
hydrogen arc involved. To take an example, the changc o f ferrous oxide
to fcrric oxide is, obviously, an oxidation; similarly, wc can regard the
changc of any ferrous compound to a fcrric compound as an oxidation
(and a changc of fcrric to ferrous as a reduction): 4FcO + 0 2 — 2Fc:Oj;
. FeCI2 + Cl2 — 2FeCb- Note that the valency o f the metal increases during
oxidation.
Metals and hydrogen form positive ions (c. g., Na' and H’) and arc,
therefore, callcd clcctropositivc. Non-metals and acid radicals arc
electronegative as they form negative ions (c. g., 0 :*, SQr')- Putting it
another way, more complete definitions o f the two terms arc:
Oxidation is the addition of any clcctroncgativc element or radical to,
or removal o f any clcctropositivc element or radical from, a substancc.
Reduction is the opposite.
An oxidizing agent is a substancc which brings about oxidation, a
reducing agent is a substancc which brings about reduction.
Oxidizing agents includc: oxygen, hydrogen peroxide, nitric acid,
sulphuric acid, chlorinc, potassium permanganate, potassium dichromatc.
Reducing agents includc: hydrogen, carbon, carbon monoxide, sulphur
dioxide, hydrogen sulphide, ammonia, and most metals and non-metals.
The equations for the oxidation o f ferrous chloridc arc:
2FcCl: + Clj — 2FcCh;
ionically: 2FAs already mentioned, the oxidation involves a changc of ferrous ion
to fcrric, it occurs by loss of an clcctron (c). And oxidation of chlorinc to
chloridc ions takes place by gain of electrons:
Fc:* - e — Fc}* (oxidation);
Ch + 2 — 2C1‘ (reduction).
To summarize, oxidation is the removal of electrons from a substancc.
Reduction is the addition of clcctrons to a substancc.
203
An oxidizing agent is a substancc that acccpts clcctrons. A reducing
agent is a substancc that supplies clcctrons.
(Remember the word ORE — Oxidation is Removal o f Electrons.)
Words and Word-Combinations to Be Memorized
agent, e. g., evolve, generally speaking, loss, meaning, monoxide, needless
to say, neither... nor, non-metal, opposite, permanganate, peroxide, put into
operation, put into pracitce, put it (in) another way, put ofT, removal, remove,
say nothing of, seem, summarize
Ex. 5. Give the Russian equivalents for the following:
the meaning o f the term, needless to say, combinc readily, a fuller
meaning, add to, remove from, apply to, take an example, obviously, regard
as, be the opposite, bring about oxidation, involve a change, by gain of
clcctrons, by loss of clcctrons, accept, supply
Ex. 6. Give the English equivalents for the following:
вообще говоря, легко соединяться, выделяться на электроде, быть
похожим на, следовательно, применять к реакции, ни... ни..., напри
мер, подобным образом, заметим что, увеличивать валентность, ины
ми словами, полное определение, азотная кислота, сульфид водоро
да, аммиак, большинство неметаллов, как уже упоминалось, удаление
электронов, окислитель, восстановитель
Ex. 7. Fill in the blanks with articles where ncccssary.
1. ... oxidation is ... removal o f ... clcctrons from ... substancc.
2
oxidation o f... chlorinc t o ... chloride ions takes placc b y ... gain of
... clcctrons. 3. ... oxygen is ... oxidizing agent. 4. ... meanings o f ...
terms ... oxidation and ... reduction arc considered here. 5 .... change of
... ferrous oxide to ... ferric oxide is obviously ... oxidation.
Ex. 8. Give synonyms for the following:
addition, readily, therefore, full, apply, take an example, changc,
obviously, regard, includc, occur, take, give
Ex. 9. Give antonyms for the following:
complex, removal, opposite, decompose, reduction, decrease, positive,
metal, incomplete, cxdude, loss, accept
Ex. 10. Translate the sentences into Russian.
1. To anticipate a little, there arc several meanings o f the terms
“oxidation” and “reduction”. 2. To be sure, any student can easily give an
example of oxidation. 3. To begin with, one can say that the simplest
meaning of the term “oxidation" is the addition of oxygen to a substancc
204
and reduction is the opposite. 4. Needless to say, this meaning is incomplete.
5. To sum up, relatively little is known about the state of solid solutions or
the conditions of equilibria which exist therein. 6. To mention only one,
wc shall consider in some detail the theory of electrolytic dissociation in
its application to homogeneous equilibria. 7. Suffice it to say that similar
results can be derived for other systems under investigation. 8. To put it in
another way, the attraction between molcculcs varies inversely. 9. To tell
the truth, these measurements vary so widely that it seems difficult to
include them in this articlc. 10. Thorium, plutonium, mcndclcvium — not
to mention uranium— belong to the actinoid series. 11. To summarize, no
satisfactory equation for the proccss has been proposed. 12. The method
is somewhat risky and not easily generalized, to say the least. 13. To put it
more exactly, these values arc now regarded as normal. 14. To say nothing
o f the details, an oxidizing agent is a substancc which brings about
oxidation. IS. Metals and hydrogen form positive ions, that is to say, they
arc electropositive. 16. To take an example, hydrogen and carbon arc
reducing agents. 17. To illustrate, a change of ferrous ion to ferric takes
placc by loss o f an electron. 18. One of the aims of education is to extend
student’s views, his philosophy, so to say. 19. As emphasized above, this
condition is satisfied automatically. 20. As already mentioned, wc find
cases where solution occurs with evolution o f heat. 21. Roughly speaking,
the conception of free ions affords very satisfactory explanation of all
these phenomena. 22. Broadly considered, a heterogeneous system is one
which consists o f more than one physical state. 23. Put another way, one
molcculc gives rise to two smaller molcculcs or atoms. 24. Strictly speaking,
it is for this reason that wc shall to a large extent limit ourselves to a brief
consideration of a gaseous state. 25. As pointed out previously, the term
“oxidation” has a long histoiy. 26. As stated above, the meaning of reduction
is the opposite o f oxidation. 27. Generally speaking, oxidation is removal
of electrons.
Ex. 11. Translate the scntcnccs into English without using a dictionary.
1. Первое, о чем обычно думают, говоря об окислении, — это то,
что окисление представляет собой присоединение кислорода. 2. Со
ответственно , восстановление — это противоположный процесс.
3. Однако теперь э л
1
термины применяются и к реакциям, в которых
ни кислород, ни водород не участвуют. 4. Современные понятия окис
ления и восстановления связаны с переносом электронов. 5. Для хи
мика окисление — это удаление электронов.
Ex. 12. Answer the following questions:
1.
What is the meaning of the term “oxidation”? 2. In what sense is
hydrogen the chcmical opposite to oxygen? 3. Why is the change of any
ferrous compound to a ferric compound regarded as an oxidation? 4. What
is an oxidizing agent? 5. What is a reducing agent? 6. What arc the most
common oxidizing and reducing agents?
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text:
of the name “oxygen”? 4. In what sense was the term “reduction” used?
4. What process was callcd oxidation?
Упр. 6. Закончите
следующие
предложения:
1.
Oxygen was discovered independently... 2. Lavoisier showed more
extensively that... 3. Lavoisier regarded an oxide as a product... 4. In
metallurgy the term “reduction” meant... 5. The nomenclature used today
was devised...
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