text:
Section III Ex. 1. Make up short dialogues according to the example.
Example:
— Where arc you from?
— I’m from Novgorod.
— Oh, I’ve never been to Novgorod, but I know it is a beautiful
town.
— Oh, yes. There are a lot of interesting places there.
Ex. 2. Respond to the following statements:
1. You know, there arc several meanings o f the word “reduction”.
2. However strange it may seem, the term “reduction” has several meanings,
too. 3. Now reduction is regarded by chemists as the addition of electrons
to a substancc.
Ex. 3. Give detailed answers to the questions.
1. Why arc the terms “oxide” and “oxidation” associated with the name
“oxygen”? 2. In what way did the terms “oxidation” and “reduction” changc
throughout the history of chcmistry? 3. What do you understand by these
terms now?
Ex. 4. Discuss the following topics:
1. The Esscncc o f the Processes of Oxidation and Reduction.
2. The Contribution of Various Chemists into the Development of
Redox Chemistry.
3. The Aspccts of Modem Redox Chemistry.


title: EMPHATIC CONSTRUCTIONS - Санкт-петербургского государственного университета высшее профессиональное образование...

text:
Analytical Chemistry — the Oldest Field of Chemistry
Analytical chcmistry is probably the oldest field in the broad spectrum
of the scicncc of chcmistry. Many years were required to dispel the lure of
alchcmy; more were needed to demonstrate the fallacy o f the phlogiston
theory. However, it was not until the brilliant Frcnch chcmist Lavoisier
(1743-1794) demonstrated, about 1785, by actual experimental methods
that combustion was a combination of a substancc with oxygen, that he
laid the basic groundwork of modem chcmistry, and, in a very particular
sense, analytical chcmistry. Indeed, he can with considerable justification
be callcd the “father” of analytical chcmistry bccausc of the great emphasis
he placcd in all experimental work on quantitative measurement. It is in
this very ncccssary characteristic of the true analytical chcmist that he
differed from Priestley (1733-1804), a discovcrer o f oxygen. Priestley, a
clergyman forced to flee from Birmingham, England, to America bccausc
of his unorthodox political and religious views, was more o f a philosopher
than a scientist.
The first problem to engage the interest o f most chcmists was to
determine as cxactly as possible the composition o f the earth. Greater
emphasis was perhaps placcd on chcmistry than physics at this stage in
the evolution o f the natural sciences — yet, the contributions o f such
scientists as Avogadro, Boyle, and Charles all had a dircct bearing and,
therefore, great usefulness in analysis. Avogadro’s law, for example, is
extremely important in the chcmistry of gases,
bccausc it docs serve as a
basis for relating weight to volume. Indeed, it is not an overstatement to
say that during the 18th and most o f the 19th ccntury the chcmistry that
did exist was largely analytical chemistry. The pinnacle of ambition of
most chcmists at that time was to be a highly successful analyst. Any
study o f chcmical literature of this period shows a preponderance of titles
related to analytical chcmistry.
It was in the latter half of the 19th ccntury that the so-callcd “industrial
revolution’’ took placc. Many beginnings (modest at first) were made in
the industrial manufacture of numerous items consumed in the household
which were traditionally produced in the home or not at all. The
raw materials in such manufacturing operations consisted chiefly o f
chemicals.
The pressing and dyeing of textiles, the production of glass, leather,
soap — these arc merely four examples (many others could be quoted) o f
operations that moved slowly out of the home and into the factory. Slowly,
but surely, this trend built up a demand for modest changcs for a limited
number of chemicals. Except for the natural dyes and tanning extracts,
most o f the industrial chcmicals produced in this area were inorganic in
nature, principally alkalies, mineral acids, ctc.
Text 32 A
209
Words and Word-Combinations to Be Memorized
area, analytical, as... as (possible), broad, chief, chiefly, consume, demand,
etc., exactly, be forced, former, highly, house, indeed, justification, laner, the
former... the latter, literature, by/in nature, not at all, operation, perhaps, press,
quote, raw, in a sense, in the sense of, stage, succcssful, successfully, title,
traditional, traditionally, usefulness, view, yet
Ex. 5. Give the Russian equivalents for the following:
the phlogiston theory, demonstrate the fallacy o f a theory, in a very
Достарыңызбен бөлісу:


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

text:
Упр. 2. Назовите значения следующих интернациональных слов:
examination, the Julian calendar, rudimentary, arrangement, vertical,
horizontal, transpose, operate, bureau, visit
Упр. 3. Определите значения выделенных слов по контексту.
1.
Mendeleyev
set down his first ideas at breakfast. 2. He received
a note about a visit to a cheese factory, but he
cancelled the visit and
worked on. 3. His mother operated a glass factory
to keep the w olf from
the door. 4. His mother
headed fo r Moscow. 5. She wanted to place her
son in the
University of Moscow, but he
was refused.
6
. The government
retired Mendeleyev from the University of St. Petersburg. 7. He bccame
head of the Bureau of Weights and Measures in 1893 and
held that post
until his death.
Слова к тексту:
devise — придумывать; brainwave — осенившая кого-л. идея; card —
карточка; juggle— манипулировать; satisfy— удовлетворять; пар— дремо
та, короткий сон; go blind — ослепнуть; lease—
арендовать;
dash— столк
новение
Text 2 В
Прочтите текст про себя (контрольное время чтения — 7 минут).
The Mendeleyev Story
In a long examination of the periodic table of the elements, the
New
Scientist for March 7 tells briefly how Dmitry Ivanovich Mendeleyev
(1834-1907) devised it. The Russian scientist had his brainwave, says
author
John Emsley, on March 1, 1869, but, bccausc the Russians were
still using the Julian calendar, it was February 17 in St. Petersburg, where
Mendeleyev lived then.
Mendeleyev set down his first ideas at breakfast, on a note he had
received about a visit to a cheese factory that day. He cancelled the visit
and worked on. He drew up several rudimentary tables, Emsley says, and
then made 63 cards, one for each of the known elements. On each card he
put the properties of the element that he thought most important. He juggled
the cards until he had an arrangement that satisfied him, wrote it down,
and went to bed. He awoke from his nap with the idea that he should
arrange the elements in vertical rather than horizontal groups and transposed
them accordingly.
Mendeleyev was bom in Siberia and was the last of 17 children. In the
year of his birth his father went blind, and his mother leased and operated
a glass factory to keep the wolf from the door. His father died in 1847, and
the glass factory burned down in 1848. With this his mother headed for
Moscow with Dmitry and his sister. Her idea was to place the son in the
University of Moscow, but he was refused bccausc he had been bom in
16
Siberia. The same thing happened in St. Petersburg, but Dmitry’s mother,
ten weeks before death got him into the Pedagogic Institute there.
The government retired Mendeleyev from the University of St. Pe-
tcrsburg in 1890 for his political activities. He was made head of the Bureau
of Weights and Measures in 1893 and held that post until his death.
Упр. 4. Скажите, что вы узнали из текста 2В; разделите его на тема
тические части и озаглавьте их.
Упр. 5. Скажите, что говорится в тексте:
1) о семье Д. И. Менделеева; 2) о том, как и куда он поступал учить
ся; 3) о том, как Д. И. Менделеев пришел к мысли о расположении эле
ментов в таблице; 4) о том, чем занимался Д. И. Менделеев в последние
годы своей жизни.
Ex. 6. Найдите в тексте и переведите на русский язык предложе
ния, в которых говорится о том, как Д. И. Менделеев воплотил свою
идею об упорядоченном расположении элементов.
Достарыңызбен бөлісу:


title: particular sense,  indeed, with justification, placc emphasis on, bccausc

text:
new elements. 5. It was not my tcachcr whom I addressed my question to.
6. It was in 1869 that Mendeleyev’s periodic system was published. 7. It is
horizontal rows of the periodic tabic which arc callcd periods. 8. Ozone
docs remove harmful ultraviolet radiation from sunlight. 9. It is not this
examination that is the most difficult this term. 10. It was not till late in the
19th ccntury that numerous household items began to be produced at factories.
11. These results do support the kinctic treatment of the behaviour ofparticlcs
in colloidal solutions. 12. It is only at ordinary temperature that the agreement
between the two methods is satisfactory. 13. It was not until the results
concerning solid solutions had been obtained that a general conclusion was
reached. 14. The reaction docs procccd slowly in most eases. IS. It was
evident that the resulting mixture did obey the mixture law. 16. The use of
deductivc methods shows that all these cases comc from one and the same
root. 17. It is not until a substancc undergoes distribution that it has the same
molecular weight in the two phases. 18. It is not until two picccs of zinc and
copper are brought into contact that they bccomc clcctrificd. 19. In the actual
case the density of the vapour docs alter with the height. 20. It was not until
oxygen was discovered that many processes could be understood.
Ex. 11.Translate the scntcnccs into English without using a dictionary.
1. Считается, что аналитическая химия— старейшая отрасль хи
мии. 2. Потребовалось много лет, чтобы показать, что теория фло
гистона неверна. 3. Развитие экспериментальных
методов внесло
большой вклад в исследование состава веществ. 4. Развитие промыш
ленности сыграло большую роль в разработке новых методов анали
тической химии. 5. Многие
операции, производившиеся ранее дома,
стали производиться в промышленных масштабах.
Ex. 12. Answer the following questions:
I .
Whose investigations helped to prove the fallacy o f the phlogiston
theory? 2. Why is Lavoisier callcd the “father” o f analytical chcmistry?
3. Why is analytical chcmistry regarded as the oldest branch o f chcmistry?
4. What problems engaged the interest o f most chcmists at that time?
5. Why did the development o f industry stimulate the development of
analytical chcmistry?
Достарыңызбен бөлісу:


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

text:
Text 32 В
Прочтите текст про себя (контрольное время чтения — 2 минуты).
Two Branches of Analytical Chemistry
The relatively small chcmical manufacturing plants producing such
chemicals as alkalis, sulphuric acid, ctc., indeed, some o f the factories
making consumer goods and employing chcmicals in the processing, soon
found it desirable to employ what was most frequently referred to as a
“works chcmist”. His duties consisted laigcly o f performing
routine tests
to determine the quality o f the raw materials coming in, so to speak, the
back door, and the finished goods going out of the front. In nearly every
instance the “works chcmist” reported to the factory manager. The analyst’s
prestige within the organization was largely that of a technician, rather
than a person considered to be professional.
The “works chcmist” or analyst of this era was conccmcd almost
exclusively with two branches of analytical chemistry, namely, qualitative
analysis and quantitative analysis. In qualitative analysis, interest is directed
to determine the constituent parts of a given product, without any effort to
determine the quantitative relationships o f these parts. Quantitative
analysis, on the other hand, as a term does very definitely indicate, is
directly concerned not only with determining the constituent parts, but
how much o f cach is present.
It is these two branches of chcmistry that arc still regarded to be
main constituent parts of modem analytical chemistry, though the methods
and apparatus used by the analytical chcmists nowadays have greatly
changcd.
Упр. 3. Передайте основное содержание текста в нескольких пред
ложениях.
Упр. 4. Какие слова в тексте означают «потребительские товары»?
Упр. 5. Найдите в тексте ответы на следующие вопросы:
1. What fields of industrial manufacture required chemists’ services?
2. What did chcmists have to do at plants and factories? 3. What branches
of chcmistry did the “works chcmist” deal with? 4. What is the diffcrcncc
between qualitative analysis and quantitative analysis? 5. Do these two
branches of analytical chemistry exist now?
Упр. б. Закончите следующие предложения:
1.
Some of the factories found it desirable... 2. The main duty of an
industrial chcmist was... 3. The analyst o f that era... 4. The aim of
qualitative analysis is... 5. Quantitative analysis is dircctly conccmcd...
6. At present, analytical chcmistry...
212
Ex. l.Makc
Example:
Ex. 2. Respond to the following statements:
1. It’s interesting to note that the very first factories and plants paid
great attention to the quality of the raw materials and finished goods.
2 .1 don’t know whether the prestige of the analyst is high in industry now,
but in the 19th ccntury it wasn’t. 3. Often, it is not sufficient to determine
what constituent parts are present in a given product.
Ex. 3. Give detailed answers to the questions.
1. What i£ the origin o f analytical chcmistry? 2. How did analytical
chcmistry change with time? 3. What arc the main constituent parts of
analytical chcmistry?
Ex. 4. Discuss the following topics:
1. The Contribution of Outstanding Scientists to the Development of
Analytical Chemistry.
2. Qualitative and Quantitative Analyses.
3. Modem Analytical Chemistry.
Достарыңызбен бөлісу:


Lesson 33
ГРАММАТИКА: Эмфатические уступительные предложения.
Section I
Ex. 1. Practise your reading.
Gradually, chcmists began synthesizing some things found in nature
and later those not found in the natural state.
Ex. 2. State what parts of speech the following words belong to:
nature, natural, unnatural, naturally, naturalist, naturalistic, naturalism,
naturalize, naturalization
Scction III
— Excuse me!
— Yes?
— Is there a canteen at the department?
— Yes, there is.
— Where is it?
— Not very far, just downstairs and round the comer.
— Thank you very much.
— That’s all right.
up short dialogues according to the example.
1. You must cxactly follow the instruction. 2. Some of the results
obtained at 25°C arc as follows. 3. Since the ratio is constant, it follows
that the molccular weight of iodine is the same in liquid as in solid benzene.
4. It is ncccssary to have a definition of science, I suggest the following.
5. This principle will be followed throughout the book. 6. Caesium and
rubidium arc of importance bccausc cacsium, followed by rubidium, is the
most easily ionized clement. 7. It follows from the above that no substancc
can be absolutely pure. 8. I’ll go first and you follow me. 9. Can you follow
my explanation? 10. The lecture will be followed by a film. 11. Following
the seminar we’ll be allowed to make our experiments.
Ex. 4. Analyse the following sentcnccs:
1. Though it may seem strange now, analytical chcmistry began to
experience a renaissance between WWI and WWII.
2. Strange as it may seem now, analytical chcmistry began to experience
a renaissance between WWI and WWII.
3. However strange it may seem, analytical chemistry began to
experience a renaissance between WWI and WWII.
Text 33 A
Classical Methods of Analysis
Strange as it may seem now, the analyst and the “works chcmist” of
the 18tli and 19th ccnturics depended almost entirely on what arc frequently
defined today as the classical methods of analysis, namely, gravimetric
analysis and volumetric analysis. Gravimetric analysis is based on methods
of determining the weights of the respective constituents of a product,
whereas volumetric analysis is based on volumes rather than weights, the
volumes being determined by a process known as titration — that is,
determination of the strength of acid and basic solutions.
Difficult as the situation of the so-callcd “works chcmist” during the
industrial revolution was, it was not the sole reason for the dcclinc of the
glamour and prestige of the analyst in the early days of the scicncc of
chcmistry.
Following the logical sequence of events, it is not at all strange that
chcmist, having taken natural substanccs apart in order to determine their
constituent elements, would then begin gradually to think about
synthesizing in a test-tube, at least some of the useful things found in
nature. The next logical step, of coursc, was to begin to think about
producing tilings not found in the natural state. Thus, wc had an evolution
of research, principally in organic chcmistry, directed towards synthesizing
old or new compounds, chicfly the latter.
About halfway between World War I and World War II, the analytical
chcmist gradually began to cxpcricncc a renaissance in his status with
Ex. 3. Define the meanings of (he word follow in the following scntcnccs:
214
other members of the profession and with management. Quality became a
very important factor in ever-increasing competitive markets. With this
welcome change there came a demand for more rapid and more accurate
methods of analysis. This demand led to a tremendous amount of research
related to the broad field o f analysis. New scientific concepts were
introduced, many of them based on what might be callcd physical chcmistry.
Words and Word-Combinations to Be Memorized
canteen, department, event, excuse, frequently, gradually, lecture, a lot of,
lots of, manage, market, profession, quality, respective, scientific, seminar,
sequence, synthesize, test-tube, thank, tremendous, tube
Ex. 5. Give the Russian equivalents for the following:
depend on the classical methods, be defined as, gravimetric analysis,
volumetric analysis, respective constituents, determine the volumes, the
strength of acid and basic solutions, a difficult situation, the sole reason,
in the early days of chcmistry, following the sequence of events, experience
a renaissance, competitive markets, introduce a conccpt
Ex. 6. Give the English equivalents for the following:
казаться странным, почти полностью, определить все, тогда как,
а не, затруднительное положение, совсем не странно, природные
вещества, чтобы определить, постепенно, синтезировать в пробир
ке, по крайней мерс, следующий шаг, таким образом, главным об
разом, химик-аналитик, потребность в новых методах анализа, ог
ромное количество исследований, основываться на, быть направ
ленным на, часто
Ex. 7. Fill in the blanks with articles where necessary.
1. I n ... volumetric analysis... volumes were determined b y ... proccss
known a s ... titration. 2. ... situation o f ... so-called “works chcmist” was
rather difficult. 3. ... evolution o f ... research led to synthesizing old or
new compounds, chiefly... latter. 4
quality became... very important
factor. 5. There came... demand for more rapid and more accurate methods
o f... analysis.
Ex. 8. Give synonyms for the following:
at present, wholly, single, start, mainly, fast, wide, idea, producc, often
Ex. 9. Give antonyms for the following:
frequently, easy, late, together, at once, useless, revolution, old, the
latter, decrease
Ex. 10. Translate the sentences into Russian.
1. Whenever an element is oxidized, some elements must be reduced.
2. Wherever sulphide ores o f the metals such as lead, copper, zinc may
215
be found, there, too, wc arc likely to find sulphur compounds of arsenic.
3. Strange as it may seem, considering its vital importance and the fact
that it is around us everywhere, conscious acquaintance with oxygen
dates back to only a little over two ccnturcs ago. 4. The energy involved
in any reaction is usually callcd the heat o f reaction, even though it may
be electrical in nature. 5. The critical temperature is the highest
temperature at which a vapour can be condensed to liquid by any pressure,
however great it may be. 6. Whenever a person working in the laboratory
mixes two or more substanccs and obtains a new product, he wants to
know what has happened and what substanccs have been produced.
7. However that may be, the agreement between the two methods is
satisfactory. 8. Important though it is, wc shall not consider this ease
now. 9. Crude though it is, this value is most frequently employed.
10. Relatively little is known about the conditions of equilibrium which
exist in the solid solution, whoever may say the opposite. 11. Whatever
these observations may appear, such solutions obey Ohm’s law, just as
metallic conductors do. 12. Simple though it actually is, this method has
the advantage of being simple and flexible and of involving usually only
moderately complicated considerations. 13. This technique remains
unreliable, although it has recently been improved. 14. Whatever you
may say, this circumstancc no doubt prevented earlier observers from
accepting the conccpt. 15. Convenient as this method is, it has a drawback
which involves a certain risk. 16. However that may be, wc may raise
the temperature and find a continuous scries o f equilibrium states.
17. Whenever a beam of white light is passed through a prism, it spreads
it out into a spectrum containing all the colours from red to violet.
18. Improbable though this case may appear at first glance, let us consider
it in detail.
Ex. 11. Translate the scntcnccs into English without using a dictionary.
1. Как это ни странно, многие методы анализа используются и
сейчас. 2. Такими классическими методами анализа являются гра
виметрический анализ и объемный анализ. 3. Химики сначала разде
ляли природные вещества, чтобы определить составляющие их эле
менты. 4. Постепенно они начали думать о том, чтобы синтезировать
некоторые полезные вещества в пробирке. 5. Затем они подошли к
следующей ступени — синтезировать совершенно новые вещества.
6. Рост требований к качеству привел к дальнейшему совершенство
ванию методов анализа.
Ex. 12. Answer the following questions:
1.
What methods of analytical chcmistry arc callcd the classical
methods o f analysis? 2. What is gravimetric analysis based on? 3. What
is volumetric analysis? 4. How did chcmists comc to the idea o f
synthesizing a substancc? 5. What stimulated the evolution of methods
of analysis?
216
|


title:
Lesson  33
ГРАММАТИКА: Эмфатические уступительные предложения.
Section I


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

text:
Упр. 3. Передайте основное содержание текста в нескольких пред
ложениях.
Упр. 4. Какие слова в тексте означают «быть непосредственно свя
занным с...»?
Упр. 5. Найдите в тексте ответы на следующие вопросы:
1. What is the position of instrumental analysis in analytical chcmistry?
2. What is the purpose of modifying instruments? 3. What is the diffcrcncc
between macroanalysis, microanalysis and trace analysis? 4. What
requirements should the sample meet to allow the analyst to obtain proper
results? 5. What is the position of the research analyst in industry or
organization at present?
Упр. б. Закончите следующие предложения:
1.
Gravimetric and volumctric methods... 2. The use o f instru
mentation.. . 3. A wide variety of new tcchniqucs have been developed...
4. A sample employed must be... 5. Now the research analyst in the
chcmical process industries...
Достарыңызбен бөлісу:


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

text:
Scction III Ex. 1. Make up short dialogues according to the example.
Example:
— Is there any acid in the bottle?
— Yes, there is.
— How much acid is there?
— There’s a lot. Shall I give it to you?
— Yes, please, bring it here.
— Here you arc.
Ex. 2. Respond to the following statements:
1. It doesn’t seem strange to me that the so-callcd classical wet methods
arc still in use. 2. The use of instrumentation is essential for modem
methods of analysis. 3. The role of the analyst in the chcmical industries is
very important now, isn’t it?
Ex. 3. Give detailed answers to the questions.
1.
What instrumental methods of analysis do you know? 2. In what
directions arc analytical methods developed? 3. Under what conditions
can the analyst obtain good results?
Ex. 4. Discuss the following topics:
1. The Role of Analytical Chemists in Various Periods of the History
of Chemistry.
2. The Development of Various Analytical Methods.
3. Working in a Team — Advantages and Disadvantages.
218


Lesson 34
Г Р А М М А Т И К А : Р а з л и ч н ы е с л у ч а и и н в е р с и и .
Scction I
Ex. 1. Practise your reading.
Used in the design and interpretation of chemical experimentation arc
various statistical methods.
Ex. 2. State what parts of speech the following words belong to:
act, actual, actually, action, interaction, acting, activc, activity, activist,
reactivity, reaction, counteraction, actor, activate, activation
Ex. 3. Define the meanings of the word extent in the following sentences:
1. The extent of the accuracy o f the instrument is rather limited.
2. Mercury undoubtedly dissolves to a certain extent in the water. 3. If
water is added to ether, solution will not occur to an indefinite extent.
4. The concentration of iodine molcculcs must decrease to a greater extent
than that of iodine atoms. 5. In liquids, the extent to which molcculcs can
move is more restricted than in gases. 6. The discovery o f the clcctron
stimulated to some extent the development of an electronic theory.
Ex. 4. Analyse the following sentences:
1. Statistical methods can never be a substitute for scicntific judgement.
2. Never can statistical methods be a substitute for scientific judgement.
Text 34 A
Statistical Methods in Analytical Chemistry
Statistical methods, as used in the design and interpretation of chcmical
experimentation, arc not a substitute for common sense or for what scientists
refer to as scicntific judgement; they rather constitute an objective aid to
judgement. In view of the mcticulousncss exhibited by scicntific workers
in the purely technical aspects of their experiments it seems appropriate to
devote some thought to two further and no less important aspects of
experimentation: its design and the final interpretation of its outcome.
Very often the experimenter designs the experiment as it proceeds, acting
on a moment’s intuition. Similarly, the interpretation or a rudimentary
study of data, the latter consisting in many cases in ranking studied cfTccts
in accordancc with their observed disturbances caused by experimental
and systcmctic errors. Naturally, even the most experienced worker is
subjcct to an occasional intuition. Therefore natural, and actually borne
219
out by the facts, is the assumption that many experiments could have
resulted in more conspicuous and sharper constructed plan.
In taking cognizancc of the unavoidable experimental eirors, rather
than in ignoring them or dismissing them as negligible, and in attempting
a mathematical study of the avoidance or the correction of systematical
errors, statisticians have succccdcd, to a ccrtain extent, in offering some
objective criteria which arc invaluable in these situations. One of the
important by-products of these methods is an estimate of the quantity of
experimental work that is ncccssary for obtaining sufficient factual proof
for a scientific hypothesis, such an estimate being more objective than the
guessing technique often used. But among the most important contributions
of statistical methodology to scicntific experimentation is the possibility
o f clearly separating the effects of various variables under study as well as
the interactions of these variables with regard to the measured quantities,
from the data resulting from a complex experiment. Hardly can it be denied
that this requires careful planning. Even before the experiment is started,
the various possible types o f results must be hypothetically considered
from the point of view of the questions under study.
Words and Word-Combinations to Be Memorized
aid, by-product, common sense, construct, construction, contribution,
correction, criterion, data, design, error, experienced, the extent to which,
mathematics, negligible, objective, occasion, offer, point of view, possibility,
proof, refer to as, statistical, statistics, substitute, succeed (in), sufficient,
sufficiently, in view of
Ex. 5. Give the Russian equivalents for the following:
be a substitute for, an aid to judgement, in the purely technical aspects,
it seems appropriate, the design of the experiment, act on a moment’s
intuition, be subject to, ignore experimental errors, the correlation of errors,
an objective criterion, obtain sufficient factual proof, guessing technique,
result from a complcx experiment, require careful planning, consider from
the point of view of
Ex. 6. Give the English equivalents for the following:
здравый смысл, ввиду многих ошибок, объяснение результато»
эксперимента, планировать эксперимент по мерс его протекания, изу
чение данных, в соответствии с наблюдаемыми фактами, опытный
исследователь, естественное предположение, приводить к экспери
ментальной ошибке, избегать систематических ошибок, статистикам
удалось сделать, быть бесценным, предложить объективные крите
рии, один из побочных продуктов, изучаемые переменные, взаимо
действие переменных, до начала эксперимента, рассматривать с точ
ки зрения
220
1. Statistical methods arc no t... substitute for... common sense. 2. Two
important aspects of ... experimentation arc its ... design and ... final
interpretation o f ... results. 3. Very often ... experimenter acts on ...
moment’s intuition. 4. Experimental work is ncccssary for obtaining ...
sufficient factual proof for... scicntific hypothesis. 5. Before... experiment
is started it is ncccssary to consider ... various possible results hypo
thetically.
Ex. 8. Give the synonyms for the following:
help, show, more, facts, supposition, take noticc of, amount, demand,
begin, kind
Ex. 9. Give the antonyms for the following:
first, the former, contrary to, incxpcricnccd, regular, take into account,
insufficient, the same, simple, after, finish
Ex. 10. Translate the sentences into Russian.
1. Students of chcmistry have to perform a number o f experiments
studying the properties of any substancc and so do students of geology.
2. Considered as isotopes arc atomic spccics having the same number of
neutrons but different mass numbers. 3. Not only docs chlorinc unite
with free hydrogen, but it has the ability to take hydrogen from
hydrocarbon compounds. 4. Only upon heating above 500°C docs zinc
'burn with a greenish flame, yielding zinc oxide. 5. No sooner is a solid
brought into contact with liquid in which it can dissolve than a ccrtain
amount of it passes into solution. 6. The first phase consists of cxccss of
phenol and a small quantity of water, so docs the second one. 7. One
liquid layer docs not contain water, nor docs the other. 8. Included in
this table arc densities of liquid and vapour. 9. Not until 1869 was this
theory put forward. 10. Neither should wc forget to chcck the purity of
the substanccs to be handled. 11. Nowhere is it so important to have
skilful hands as in a chcmistry laboratory. 12. Never is it so important to
think about style as in writing a textbook. 13. Never has more accurate
result been obtained. 14. He was always ready to answer any question
and so was his friend. 15. Hardly had wc heated the test-tube several
minutes when an explosion suddenly happened. 16. Important for this
conclusion is the arrangement of atoms in the molcculcs. 17. Correlative
with the hypothesis arc the results of the latest series of experiments.
18. Great arc differences in selectivity between intermediates. 19. Plotted
in Figure 5 is the variation of selectivity.
Ex. 11.Translate the sentences into English without using a dictionary.
1. Очень важными в аналитической химии являются статистичес
кие методы. 2. Едва ли можно сказать, что планирование экспсри-
Ex. 7. Fill in the blanks with articles where ncccssary.
221
мента — простое дело. 3. Объяснить конечный результат реакции
бывает непросто и опытному химику. 4. Ученым удалось выработать
некоторые методы, чтобы избежать ошибки при проведении экспе
риментов. 5. Объективными критериями правильности научной ги
потезы можно считать только факты.
Ex. 12. Answer (he following questions:
1. In what fields of analytical chcmistry can statistical methods be
used? 2. What important aspects of experimentation should be taken into
account? 3. What is the role of intuition in experimentation? 4. What must
be the attitude to errors? S. What is regarded as the most important
contribution of statistical methodology to scicntific experimentation?
Достарыңызбен бөлісу: |


text:
analytical balancc. Results to six significant and cxact figures arc
ordinary.
Those who have learned about balances by an intuitive proccss tend
to think of them as tcctcr-tottcrs. Actually a balancc is a compound
pendulum with complications. The essentials of the operation can be
understood easily, however, by visualizing an upright
wheel free to tum
on a fixed axle...
Упр. 3. Передайте основное содержание текста в нескольких пред
ложениях.
Упр. 4. Какое слово в тексте означает «искусный, умелый»?
Упр. 5. Найдите в тексте ответы на следующие вопросы:
1. When docs analytical balancc bccomc a useful tool in the
laboratory? 2. What is the attitude o f students to the use o f analytical
balancc? 3. What measurements arc regarded as fundamental? 4. What
is the characteristic feature of analytical balancc? 5. What is the design
of the analytical balancc?
Упр. б. Закончите следующие предложения:
1. Analytical balancc is... 2. Chemistry students arc conccmcd with...
3. Some students avoid using a balancc bccausc... 4. The balancc can be
used to prepare standards for... 5. Usually, a balancc is thought to be...
Достарыңызбен бөлісу:


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

text:
Section III Ex. 1. Make up short dialogues according to the example.
Example: — Can 1 help you?
— Yes. I’d like some information about foreign journals on
chcmistiy in this library.
— What field of chemistry arc you interested in?
— Nature compounds.
— Let’s use the computer, we’ll find all the information you need.
Ex. 2. Respond to the following statemets:
1. Statistical methods arc used not only for the design o f expe
rimentation. 2. To my mind, intuition is not important for chcmists.
3 .1 don’t think the balancc is the most essential tool in a chcmical
laboratory, there arc many others.
Ex. 3. Give detailed answers to the questions.
1.
What methods arc used in analytical chcmistry? 2. What must
students be able to do in a laboratory? 3. What aspects must be taken into
account in planning experiments?
Ex. 4. Discuss the following topics:
1. Interpretation of Experimental Results.
2. Designs of Modem Analytical Balances.
3. How to Avoid Errors in Experimentation.
4. How to Estimate Experimental Errors.


title:
Lesson  35
ГРАММАТИКА:  Предложения с  парным  союзом  the...  //ic...  .  Двойное
отрицание.
Scction 1

text:
of the extra-nuclear clcctrons was restricted to an indication that their
number must equal the atomic number of the element, and to a mention of
the fact that they form a relatively open structure about the ccntral nucleus.
The question of their arrangement must now be discussed in detail, and in
this conncction valuable information has been obtained from an
examination of both optical and X-ray spcctra, the
former term being used
to describe spcctra in the ultraviolet, visible and infra-red regions.
When a solid is heated to incandcsccncc, it emits a more or less
continuous spcctrum, but gases and vapours under the same conditions,
when examined spectroscopically, show a scries often very complicated,
of distinct lines or bands occupying definite positions, that is, with definite
wave lengths. The more information conccming the composition o f
various spcctra was obtained, the clcarcr it bccamc that the line spcctra
arc produced by atoms and so arc not unfrcqucntly referred to as atomic
spcctra, whereas the so-called band spcctra, which can, in fact, often be
resolved into large number of closely spaced lines, arc obtained from
molcculcs.
A line spcctrum is the one formed when radiation from an incandcsccnt
gas is passed through a slit and then dispersed. The lines arc produced by
energy changes when clcctrons pass from high energy
quantum levels to
low energy quantum levels. The clcctrons arc cxcitcd from low to high
levels by the input of energy into the gas — usually in a discharge tube
under a high voltage.
In a molccular spcctrum, a scries of fairly broad bands is formed. These
bands arc sharp at one edge but dying away on the other. They arise from
the complex energy changes possible in a molcculc. Under high resolution,
the band is shown to be made up of many lines sharper and clcarcr together
at the head of the band but more diffuse away from the head of the band. It
seems not at all unlikely that the more complcx the molcculc, the more
complicated the spcctrum is.
It is from atomic spcctra in particular that information conccming the
cxtra-nuclcar clcctrons has been obtained.
Words and Word-Combinations to Be Memorized
band, complicated, concerning, on/under condition, conncction, in
conncction with, diffusion, disperse, edge, emit, examination, cxcite, extra, in
fact, the fact that, head, incandcsccnt, infrared, investigate, length, most likely,
not likely, nuclear, optical, in particular, pass, radiation, radiate, slit, spectroscopy,
the... the..., unlikely, voltage
Ex. 5. Give the Russian equivalents for the following:
a profound investigation, restrict consideration to, mention the fact, in
this conncction, examine a spcctrum, heat to incandesccncc, examine
spectroscopically, a distinct line,
resolve into a number of lines, pass from
one level to another, cxcitc clcctrons, by the input of energy, in a discharge
8 Степаном
225
tube, a scries of bands, arise from energy changes,
under high resolution,
information conccming extra-nuclear electrons
Ex. 6. Give the English equivalents for the following:
равняться атомному номеру элемента, относительно открытая
структура, расположение электронов, оптический спсктр, в инфра
красной области, испускать непрерывный спсктр, при тех же услови
ях, занимать определенные положения, длина волны, получать ин
формацию, линейный спсктр, близко расположенные друг к другу
линии, раскаленный газ, пропускать через щель, высокое напряже
ние, на
одном конце, в частности
Ex. 7. Fill in the blanks with articles where ncccssary.
1
more is known about... spcctra,... more questions arise. 2. When
... solid is heated to ... incandcsccncc, it emits ... spectrum. 3. ... line
spcctra arc produced b y ... atoms. 4 .... electrons arc excited in ... discharge
tube under... high voltage. S
information conccming... extra-nuclear
electrons has been obtained particularly from ... atomic spcctra.
Ex. 8. Give synonyms for the following:
examination, be limited to, question, important, evolve, a number of,
dear, actually, get, give, likely, complcx
Ex. 9. Give antonyms for the following:
disappear, rcccntly, closed, different, indefinite, small, low, simple
Ex. 10. Translate the sentences into Russian.
1.
It is not unusual to consider elements from the point of view of their
properties. 2. Not unfrcqucntly water itself acts as a catalyst in many
reactions. 3. The higher the temperature, the greater is the viscosity of
gases. 4. The greater the number of carbon atoms
in a given structure, the
more ways there arc for arranging them. 5. The smaller the chargcs carried
by the ions of a crystal and the larger the ionic radii, the weaker the forces
that bind the ions to one another within the crystal, and the more readily
the crystal structure is broken down. 6. It is not improbable that the results
of their work will be similar to ours. 7. Vaporization proceeds faster, the
higher is the temperature, pressure being constant. 8 .1Ъс results will be in
closer agreement, the more strictly the instruction is followed. 9. The
accuracy of weighing is not inconsiderably influenced by the sensitivity
o f the balance used. 10. Under these conditions concentration is higher,
the higher the temperature. 11. The harder you study, the better you master
the subject. 12. The reaction is more efficient, the purer the chemicals.
13. The smaller the number of the element, the lighter it is. 14. The greater
the quantity of heat possessed by the body, the greater is its hotness. 1 5. The
earlier the history of chcmistry, the more striking it is. 16. Not unfrcqucntly
the word has several meanings, c. g., the word “theory". 17. It seemed not
226
improbable that some elements occur as a mixture of isotopes in nature.
18. It is not at all unlikely that new elements will be discovered. 19. The
properties of the element are not inconsiderably influenced by their atomic
number. 20. The atomic weights of elements are not uncommonly revised
after thorough studies in laboratories.
Ex. 11. Translate the scntcnccs into English without using a dictionary.
1. Существует множество
методов изучения структуры атомов и
молекул. 2. Ценную информацию в этой связи можно получить из
исследования спектров. 3. Ученые различают спектры атомов и мо
лекул. 4. Атомы дают линейные спектры. 5. Молекулярные спектры
называют полосатыми.
Ex. 12. Answer the following questions:
1. What information can one obtain from an examination o f spcctra?
2. What kinds o f spcctra arc known? 3. When docs a solid emit a
spcctrum? 4. Under what condition docs a gas emit a spcctrum? 5. What
spcctrum is callcd linear? 6. What is the difference between linear and
band spcctra?
Достарыңызбен бөлісу:


text:
He pointed out that the method could be used to determine the composition
of celestial bodies, thus laying the foundation for the application of the
spectroscope in astronomy, among the modem scicnccs. He even callcd
attention to the possibility of detecting impurities in a metal by this method,
thus speaking the language of the most up-to-date spcctrographcr.
The only possible claim to priority over Altcr’s discovery can be made
in behalf of Sir John Hcrschcl, who in 1824 demonstrated the possibility
of detecting small quantities o f an alkali by its flame spcctrum. However,
this work was described in an inaccessible journal, thus receiving practically
no publicity. Unfortunately, it is not unfrcqucntly that this happens. That
is why scientists usually seek to publish their papers in prestigious journals:
the better the reputation of the journal, the sooner the information it contains
comes to the reader. Furthermore, confuscd by the continual presence of
the strong orange lines, later found to be sodium lines. Hcrschcl soon
regarded his own discovery as incorrect. The same prevalent sodium lines
kept other physicists of that time from realizing that each element has its
characteristic line in the spcctrum.
Alter, however, was not obstructed by this stumbling block. Neither
did the lack of scicntific instruments discourage him. He ground his own
prism and constructed his own apparatus.
Упр. 3. Передайте основное содержание текста в нескольких пред*
ложенпях.
Упр. 4. Какое слово в тексте
означает
« у д е р ж и в а т ь ,
мешать»?
Упр. 5. Найдите в тексте ответы на следующие вопросы:
1. What will surprise those who study the history of spcctrum analysis?
2. What conclusion did David Alter comc to? 3. How did it happen that
John HcrschcPs work remained unknown? 4. Why do scientists try to
publish their papers in well-known journals? 5. What prevented Hcrschcl
from drawing the right conclusion?
Упр. 6. Закончите следующие предложения:
1.
Five years prior to the work of Kirchhoff... 2. Alter pointed out
that... 3. He callcd attention of other scientists to... 4. The priority of
Hcrschcl’s work is shown by... 5. Hcrschcl was confuscd...
Достарыңызбен бөлісу:


text:
Section III Ex. 1. Think of the situations when the following expressions may be
used:
to my mind; I don’t think so; I agree with you; it’s (quite) right; it’s not
right; sorry, you arc wrong
Ex. 2. Express your agreement or disagreement with the following
statements. Use expressions from exercise 1.
1. Mendeleyev was the only scientist who tried to arrange the elements.
2. A lot of new elements were predicted with the help of the periodic
table. 3. To commemorate Mendeleyev, the Soviet researchers named many
newly discovered things after him. 4. The periodic system didn’t change
with time. 5. Mendeleyev was interested only in chcmistry.
6
. Mendeleyev’s
family was small. 7. Mendeleyev got his education in St. Petersburg.
Ex. 3. Make up sentences or short stories with the following words and
expressions:
1
)
be bom, children, year, father, mother;
2
) head, hold the post, bureau;
3) periodic system, serve, contribution, study; 4) the element, bear the
name; 5) devote, teaching, development, economy, progress
Ex. 4. Give detailed answers to the following questions:
1.
How did D. I. Mendeleyev devise his periodic table? 2. What is the
importance of the periodic system of the elements? 3. Why do people call
Mendeleyev "the greatest chcmist of the world”? 4 Whai Лгтггк of
Mendeleyev have come true nowadays?


text:
Ex. 2. Respond to the following statements:
1. I’m not interested in the history of this or that phenomenon, the
csscncc of it is the thing that matters.
2
. It’s not so easy to distinguish
between various spcctra. 3.1 think spectroscopy is a very interesting Held.
Ex. 3. Give detailed answers to the questions.
1.
What do you know about the contribution o f scientists to the
development of spectrum analysis? 2. What kinds of spcctra are known
today? 3. How can they be obtained?
Ex. 4. Discuss the following topics:
1
. Modem Methods o f Analysis dealing with Spcctra.
2. The Importance o f Spectral Analysis for Analytical Chemistry.
3. The Application of Spectral Analysis in Sciences Other than
Chemistry.
Достарыңызбен бөлісу:


Lesson 36
ГРА М М А ТИ КА : Обш се повторение.
Scction I
Ex. 1. Practise your reading.
The guiding light o f theory must be confirmed by the bench of physical
manipulation.
Ex. 2. State what parts of speech the following words belong to:
general, generally, generalize, generalized, generalization, generality
Ex. 3. Define the meanings of the word question in the following sentences:
1
. Not cvciy question can be answered at once. 2. The phenomenon in
question is exactly analogous to those already described. 3. That water consists
of oxygen and hydrogen is beyond question. 4. There is no question but that
sulphuric acid is much stronger than sulphurous acid. 5. Naturally, the
question arises as to the role of the solvent.
6
. This is a questionable point of
view. 7. That both these results arc devoid of error is out of the question.
Ex. 4. Analyse the following scntcnccs:
1
. A burner is on my table. 2. There is a burner on my table. 3. The
burner is on my table.
Text 36 A
C hoosing C hem istry a Profession
The students enrolled for a course in general chcmistry can and do ask
themselves the question: “What real use is this course to me?”
229
The answer for the student who intends to major in a scicncc is obvious.
His hope is to derive information to use as a tool in making a living.
There is an answer, however, beyond the fact that the coursc may be
required.
The period of the teens and early twenties is a crucial one in life. It is
during this time that the student is approaching intcllcctual and emotional
maturity and is physically in his prime. It is also at this time that he is
striving to discover what meaning and purpose there may be in life; he is
about to comc to the conclusion that other people actually exist as important
entities rather than adjuncts to his personal welfare; and it is now that with
freshly opening eyes he seeks to put the world into an understandable
perspective. At no other time than this is the mind so supple and so capablc
of amendment.
If there is any real lack peculiar to the age, it is the lack of all kinds of
experience. Years at college should provide the social and personal
cxpcricnccs to fill this gap. The first year at collcgc may also be one of
keen disillusionment, as the student discovers that the professors arc not
the gods who hold the final answers to all being and meaning in their
august persons.
The particular and important scrvicc that the chcmistry tcachcr can
make is the contribution o f facts to the building materials of personal
philosophy. Certainly, the best and finest house requires the most materials
for its construction, and the most complete and satisfactory o f personal
philosophies must be housed in a framework of fact, however gaudily it
may later be dccoratcd with the furniture of speculation.
This wc can do: provide the student with some ideas conccming the
structure of matter, the finitcness of the kinds of matter, and the changes
matter can undergo. To this, it is hoped, may be added an appreciation for
the orderliness of nature and simple laws which govern the infinite
proliferation of her works. One should be careful to present known facts
as the facts of experience and experiment and stress the idea that the guiding
light of theory must be confirmed by the bench of physical manipulation.
Words and Word-Combinations to Be Memorized
be about, age, beyond, certainly, conclusion, fill, framework, fresh, gap,
govern, guide, infinite, intend, tack, major, other than, person, philosophy,
purpose, real, service, tool
Ex. 5. Give the Russian equivalents for the following:
intend to do smth., derive information, make a living, the period o f
the teens, a crucial period, intcllcctual maturity, be about to conclude,
personal welfare, be capablc o f amendment, the lack of all kinds o f
experience, years at collcgc, fill the gap, provide smb. with smth., to
undergo changes, the orderliness of nature, guiding light o f theory,
physical manipulation
230
выбирать профессию, курс общей химии, очевидный ответ, на*
дежда получить информацию, цель в жизни, личное благополучие,
недостаток опыта, важная услуга; идеи, касающиеся структуры ве
щества; простые законы, следует быть осторожным, представлять
факты как..., подчеркивать мысль, подтвердить факт, удовлетвори
тельное объяснение
Ex. 7. Fill in the blanks with articles where ncccssary.
1
— student hopes to derive... information to use a s... tool in making
... living. 2 .... period of the teens and early twenties is characterized by
... lack of all kinds o f ... experience. 3 .... first year a t ... college may be
... period o f ... disillusionment. 4
student discovers th a t... professors
are n o t... gods. 5— chcmistry tcachcr can provide... student with some
fundamental ideas concerning ... matter.
Ex. 8. Give synonyms for the following:
actual, aim, apparent, obtain from, comc nearer, too, find out, try to,
give, of course, nice, thought, emphasize, lead
Ex. 9. Givp antonyms for the following:
ask, late, comc, now, with, excess, best, earlier, careless, finite
Ex. 10. Translate the sentences into Russian.
1. The methods cmplycd depend upon the system under consideration.
2. It is owing to the dissociation o f acetic acid that the solution bccomcs
alkaline. 3. Discussed in the prccccding chapter is the behaviour of
systems formed of two components. 4. It is not improbable that the ratio
o f the concentrations of a given substancc, distributed between two
phases, will be constant. 5. It is not until the solution forms a column of
height h that water enters the tube.
6
. Neither can one suppose that the
vapour obeys the law'. 7. Sodium acetate in water docs undergo a partial
decomposition.
8
. Given in the following table arc the values of the
solubility. 9. To be sure, the most interesting thing about the conduct of
hydrogen is its affinity for oxygen. 10. Putting it another way, the reverse
proccss to that of oxidation is callcd reduction. 11. Although there can
be at least as many alcohols as there arc hydrocarbons, only a few of
these are of importance. 12. Generally speaking, not all chcmical reactions
arc accompanied by a release of energy. 13. Kinctically, chcmical activity
is due to collisions o f the molcculcs o f the reacting substanccs.
14. Surprising as it may Seem, compounds containing the sodium ion arc
almost ccrtain to be soluble. IS. The greater the acidity, the greater is
the capacity for holding anions. 16. To sum up, the halogens, as a group,
form one of the most striking examples of family relationship found in
the periodic table. 17. Generally speaking, it is among the spontaneous
Ex. 6. Give the English equivalents for the following:
processes of nature, many of them chcmical, that wc find energy for
doing our work. 18. A changc in velocity is callcd an acceleration. 19. The
greater the applied force, the greater the changc in velocity — that is to
say, the greater the acceleration.
Ex. 11. Translate the scntcnccs into English without using a dictionary.
1. Обычно человек становится студентом, если он надеется зани
маться наукой или получит>> информацию, которую он может исполь
зовать, чтобы зарабатывать себе на жизнь. 2. Юность — самый бла
гоприятный период для этого. 3. Иногда в первые годы обучения
студент испытывает разочарование. 4. В этом случае желательно по
думать, правилен ли был выбор профессии. 5. Одна нз основных це
лей образования — ознакомиться с фундаментальными теориями и
новыми идеями в избранной области.
Ex. 12. Answer the following questions:
1. What question do students often ask themselves? 2. Why is the
period of the teens and early twenties regarded as a crucial period of one’s
life? 3. Why may the first year at collcgc be the period of disillusionment?
4. What service can the chcmistry tcachcr make? 5. What knowledge is
the chcmistry student provided with?
Достарыңызбен бөлісу: |


text:
It is easy to attack any specific coursc as contributing little or nothing
that the student will use after graduation. However, the huge reality and
meaning of education lie precisely in that web of concepts and attitudes
which have no meaning without factual detail. It is of no importance that
the scaffolding of empirical facts disappear after the edifice wc call
education has been erected.
It is not wise to press the analogy too far. Beside this complex o f
attitudes and ideas we have callcd philosophy, or education, there is
necessarily gained by the student a good deal of knowledge which might
be characterized as off-hand knowledge in the sense that it is immediately
present and usable whenever callcd up. Such is the knowledge the
engineer uses in the practicc of engineering and his information in the
arts and literature which he may use in ordinary conversation. This
immediately available information is tool and culture material and its
acquisition is defensible.
But what of that information which has been lost unused, is other than
scaffolding? Tlic answer is that it has not been lost. Material which has
sunk below the level of recall may be much more easily relearned and
understood than brand-new material. The foundations have been built and
lie in readiness for the possible time when a particular skill is to be
developed. This non-recall information is thus not useless, even though a
great part of it be unused. It might be pointed out that even tool information
is largely sunk below the level of recall. Especially in chcmistry, though a
man has
a million facts in his head, he still needs the reference literature.
The unique value of a coursc in chcmistry is that it is the only coursc
taken by the great majority of students in which they learn the structure
and behaviour of the matter of which their environment is composed. Each
knowledge is o f primary importance in the development of any realistic
philosophy or the understanding of nature.
Упр. 3. Передайте основное содержание текста в нескольких пред
ложениях.
Упр. 4. Какие слова в тексте означают «знания, которые вссгаа с
тобой»?
Упр. S. Найдите в тексте ответы на следующие вопросы:
1
. Docs the student remember everything he learns? 2. What may any
specific coursc be criticized for? 3. What kind of knowledge docs the
student gain? 4. What may be the example of off-hand knowledge? 5. What
is the use o f information which seems to be lost?
6
. What is the unique
feature of a coursc in chcmistry?
Упр. б. Закончите следующие предложения:
I.
Wc may be troubled if... 2. The essence of education is... 3. The
foundations lie in readiness... 4. Though a person has a million facts in
his head, he... 5. Chemistry coursc is of primary importance bccausc...
233


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

text:
Scction III Ex. 1. Make up short dialogues according to the example.
Example:
— Ah. good evening, Mike! 1 never see you at the'faculty
nowadays.
— Yes, wc used to meet on Wednesdays, but now my time
table has changcd.
— Has it?
— Yes, now I have classes in St. Petersburg, not here on
Wednesdays.
— I see.
Ex. 2. Respond to the following statements:
1. Choosing a profession is not an easy thing, you know. 2. As for
me, I like chcmistry most of all. 3. I’m sorry to say, but 1 forget a lot of
what I learn.
Ex. 3. Give detailed answers to the questions.
1
. What do people expect to gain from education? 2. Why is it ncccssary
to Icam even those things which won’t be used immediately? 3. Why is
chcmistry one of the most useful professions?
Ex. 4. Discuss the following topics:
1. Possible Ways of Choosing a Profession.
2. The Purpose of Higher Education.
3. Chemistry as a Profession.


title: TRANSLATION PRACTICE - Санкт-петербургского государственного университета высшее профессиональное образование т....

text:
TRANSLATION PRACTICE
Texts
Text 1
Conductance and Electrolysis
Generally speaking, the classification of a substancc as a non-clcctrolytc
or as an cicctrolytc is based on the conductance of its aqueous solution.
Aqueous solutions of non-clcctrolytcs do not conduct an clcctric current
to any greater extent than pure water docs, whereas aqueous solutions of
electrolytes conduct an clcctric current and undergo clcctrolysis. Weak
clcctrolytcs give solutions which arc relatively poor conductors bccausc
of a limited degree of ionization. On the other hand, aqueous solutions of
strong clcctrolytcs readily conduct an clcctric current.
If a strong cicctrolytc is formed as a result of a chcmical reaction
involving two weak clcctrolytcs, the conductancc of the resulting solution
increases. If the ions of a strong cicctrolytc are removed from solution as
an insoluble precipitate, or from a weak cicctrolytc with the ions of another
reactant, the conductancc of a mixture of the reactants is less than that of
the strong cicctrolytc. After the reaction is complete, the conductancc will
increase upon further addition of the second reactant, provided the latter
is a strong cicctrolytc.
Electrolysis always accompanies the passage of a direct current through
an aqueous solution. Cations arc rcduccd to a lower oxidation state, some
of them to the free state, at the cathodc; anions arc oxidized to ions with a
higher oxidation state, or to the free state, at the anode.
Text 2
Library* and You
Bccausc of the vast accumulation of data, today’s student of chcmistry
must rely on the literature more than ever before; it is therefore to his
advantage to bccomc acquainted with the organization and proper use of
the chcmical literature at the earlier stage of his training. A good way of
235
helping him to accomplish this in an informal fashion is to cncouragc him to
acquire for his own collcction a core of rcfcrcncc books. A great number of
undergraduates as well as graduate students arc not aware of the wealth of
information available in basic rcfcrcncc tools such as dictionaries and
handbooks, simply bccausc they arc not in the habit of regularly consulting
them. By owing a number of these relatively inexpensive reference tools,
the student will have a great deal of information at his fingertips, and through
constant use of it will develop good library habits which will not only benefit
him throughout his professional career but also reduce his tendency to
memorize material which he can readily obtain from these books.
Text 3
Infrared Spectroscopy
Infrared spectroscopy resembles Raman spectroscopy in that it provides
information on the vibrational and rotational energy levels of a species, but
it differs from the latter technique in that it is based on studying the light
transmitted through a medium after absorption, and not that scattered by it.
The techniques of Raman and IR spectroscopy arc generally considered
complementary in the gas and solid phases bccausc some of the spccics
under study may reveal themselves in only one o f the techniques.
Nevertheless, it must be stressed that Raman scattering is not affected by
the aqueous medium, whereas strong absorption in the infrared shown by
water proves to be a troublesome interfering factor in the study of aqueous
solutions by the IR method.
Text 4
Nuclear Magnetic Resonance
The nuclei of atoms can be likened in some respccts to. elementary
magnets. In a strong magnetic field, the different orientations that the
elementary magnets assume correspond to different energies. Thus,
transitions of the nuclear magnets between these different energy levels
correspond to different frcqucncics of radiation in the short-wave, radio-
frequency range. Hence, if an electrolytic solution is placcd in a strong
magnetic field and an oscillating clcctromagnctic field is applied, the
nuclear magnets exchange energy (exhibit resonant absorption) when
the incident frequency equals that for the transitions of nuclei between
various levels.
Were this NMR to depend only on the nuclei of the spccics present in
the solution, the technique would be without point for the identification of
spccics in a solution. But the nuclei sense the applied field as modified by
the environment of the nuclei. The modification is almost exclusively due
to the nuclei and electrons in the neighbourhood of the sensing nucleus,
i. c., due to the adjacent atoms and bonds. Thus, NMR studies can be used
236
lo provide information on the type of association between an ion and its
environmental particles, c. g., on ion-solvent interactions or ion association.
Text 5
Gold
Perhaps no other metal has played such an important part in the destiny
of man as gold has. For centuries, it has stood as a barometer of wealth
and nobility. To secure it, men have fought, suffered and died. Countries
have been founded through the search for it; kingdoms have been lost
bccausc of it.
Why?
Well, wc can supply three reasons. Value. Beauty. Pcrmancncc.
Obviously, there is a limited supply of the metal available which increases
its value. The fact that it is usually found free in nature makes it easy to
mine — if you can find it. That it is attractive, wc cannot deny. There arc
very few people who do not appreciate the warm, shining yellow beauty
of gold. (Wc would greatly appreciate having some.) And, finally, its
appcarancc is quite permanent. Aluminium bccomcs dull, iron rusts, coppcr
corrodes, silver tarnishes, but gold remains the same. (Although, it must
be dusted occasionally.)
Despite our glowing words above, metallic gold has very few practical
uses. It is really a metal to be looked at, not to be used, about its only use
at present is in the manufacture o f jewellery. And even then it must be
alloyed with other metals, usually coppcr or silver, as it is too soft to be
used in the pure state.
Gold is inactive and is not attacked by oxygen or ordinary acids. It
docs, however, react readily with chlorinc to form gold (auric) chloride,
AuClj. Thus, wc can dissolve it in aqua regia or chlorinc water, both o f
which supply chlorinc.
It is owing to its remarkable properties that gold as well as platinum
arc increasingly used in some fields where particular accuracy and
reliability arc needed.
Text 6
Actinium
Radioactive transition metal o f Group III. Atomic number 89. Symbol
Ac. All isotopes arc radioactive; atomic weight tables list the atomic weight
as [227], the mass number of the most stable isotope.
Actinium is exclusively tripositivc and resembles the tripositivc rare
earth elements in its chcmical properties. It forms insoluble compounds of
the same type as the lanthanide elements, such as the fluoride and oxalate.
The hydroxide is also insoluble. The similarities to the lanthanides appear
in the crystallization of double salts, such as, for example, with magnesium
237
nitrate, where actinium follows the lanthanides and is very difficult to
separate from them. Differences from the lanthanides are to be found in
the extent to which complex ions arc formed, actinium being, in general,
less easily subject to complex ion formation than any of the lanthanide
elements. This is presumably related to the basic or clcctropositivc charactcr
of actinium, a consequence of its laigcr ionic radius, and it appears that
actinium is more basic than even lanthanum. Actinium goes with cerium
group of rare earths in those separations in which the yttrium group is
separated with the help of complcxing agents. The succcssful separation
of the lanthanide elements from each other by use of the ion exchange
resins is also applicable to the separation of actinium from the lanthanide
elements and the heavier tripositivc actinide elements.
Except for the sulphide, the compounds o f actinium arc colourless.
All of the pure compounds o f actinium which have been prepared and
whose structures have been determined arc isostuctural with the analogous
lanthanide and actinide compounds and in each the actinium is tripositivc.
In addition to the solid halides and oxyhalidcs, a number o f other
compounds such as scsquioxidc, sulphide, phosphate, oxalate, and a double
salt with potassium sulphate have been prepared.
Text 7
Radiation Effects on Polymers
Radiation exerts two opposing effects on polymers. On the one hand,
it breaks up the polymer molcculcs into smaller picccs. On the other, it
causes liberation of a hydrogen atom from each of the two adjoining
molcculcs with formation o f a link between the two molcculcs (cross-
linking). The existence of cross-links in a polymer makes the material
tougher and higher melting and is very desirable for certain applications.
The cross-linking o f polymers by radiation has been much studied.
The irradiation of any organic compounds results in breaking ofCH bonds,
leaving free bonds on the carbon atoms while the hydrogen atoms go off*
together in pairs to form hydrogen gas. In a liquid the resulting free radicals
can diffuse as a whole through the solution and eventually meet together
and combinc. In a solid polymer it is not dear how these centers get together.
One proposed mechanism is that a hydrogen atom from a neighbouring
carbon will pop into the vacatcd hydrogen spacc, producing a new free
bond on the atom adjaccnt to the original free bond position. This proccss
will continue, with the free bond flowing up and down the chain, until the
free bond happens to find itself next to a free bond formed on the adjaccnt
molecule which is likewise travelling up and down. Another mechanism,
possible perhaps only with amorphous polymer, is that the long-chain
molcculcs as a whole may move with respect to one another until the free
bonds find themselves in proximity.
Whatever the mechanism of cross-linking may be, the result is of
commercial value.
238
Text 8
Л Metal that Doesn’t Sink
A little plate of greyish metal was as light as a chip o f wood and
didn’t sink in water. It was a sample of a magncsium-lithium alloy
developed at the A. Baikov Metallurgy Institute of the USSR Academy
of Scicnccs.
Silver-white magnesium is lighter than aluminium and superior to it
in heat capacity and in its capability to act as the main component of various
structural materials. It is, in fact, 1.5 times lighter than aluminium and 4.S
times lighter than iron. It doesn’t give off sparks from friction or on being
struck, and is easy to work and weld with, electrically or using gas.
Magnesium is also one of the most widespread metals. Its resources arc
dozens of times higher than those of nickcl, zinc, and lead.
As for lithium, the third clement on the Mendeleyev periodic table, it is
the lightest of all metals. Everything new and unusual appearing today in
metallurgy, chcmistry, and power-engineering is to a large extent conncctcd
with lithium. Scientists, engineers and inventors placc great hopes on it.
According to expert opinion, there is much more lithium in the earth’s
crust than, say, zinc or tin, 130 times more than cadmium and 160 more
than antimony. Another interesting fact: over the past 25 years alone, the
production of lithium metal in the West has increased 100-fold. Obviously,
there is no shortage of lithium in the world.
The installation used to producc magncsium-lithium alloys is an
elcctrically-hcatcd crucible. After definite proportions of magnesium and
lithium foundry pigs arc put into it, the crucible is hermetically scaled
and all air pumped out of it. Then the crucible chamber is filled with
argon, an inert gas. Melting, pouring and cooling arc all done in an airless
medium.
The new alloys will be widely used in these branches of engineering
where lightweight metals arc required to producc machine parts, equipment,
instruments, and household articles.
Text 9
Insulator Itarns into Superconductor
Having used ultrahigh pressures and critically low temperatures,
scientists at the Institute of High Pressures of the USSR Academy of
Scicnccs have managed to cffcct such a unique transformation as converting
a sulphur insulator into a superconductor...
Superconductivity, at which a conductor completely lacks resistance
to elcctric currcnt, was discovered more than 70 years ago. This
phenomenon occurs at temperatures around -273°C.
Present-day electronic, clcctrotcchnical apparatuses, instruments and
machines have been developed, operating on superconductors under
239
conditions of low temperatures. Among them arc radio-receiving dcviccs
for detecting weak signals arriving from the depths of outer spacc, highly
cfTicicnt powerful, and yet small, current generators, transformers and cablcs.
The equipment that uses superconductors is expensive and is not
available for users at large. That is why scientists arc looking for materials
which would bccomc superconducting at a temperature of, for example,
liquid hydrogen, which is -252°C, or liquid nitrogen, which is -196°C.
Sulphur has been quite unexpectedly found among the superconducting
materials.
The main unit of this installation is a high-pressure chamber. It contains
two anvils of synthetic polycrystallinc diamond, “carbonado” or black
diamond. The surfacc of one anvil is flat, whereas the other one is shaped
as a cone. When comprcsscd, the anvil point develops a pressure of half a
million atmospheres! Under such conditions sulphur converts to a
“metallic” formation. “Metallic sulphur”, cooled by liquid helium, acquires
superconducting properties at a temperature of-269°C.
Experiments arc being continued and have so far yielded interesting
results. Sulphur has increased the temperature o f covcrsion into a
superconducting material to -242°C.
Up to now a champion in high temperature superconductivity has
been a niobium-to-gcrmanium compound. Its conversion temperature
into a superconducting state was -2S0°C. Now the leadership has passed
over to sulphur.
Text 10
Salt Shaker Wedding
On Friday evening, April 13, at five o’clock, Miss Chlorinc Halide
became the bride of Mr. Sodium Alkali in a double beaker ccrcmony at
the Little Church o f Mother Nature. Rev. Electro Valcncc performed the
ccrcmony.
The bride was given in marriage by her unclc, Mr. Argon Inert, one o f
the community’s most prominent bachelors. The bride’s eldest sister Miss
Iodine Halide, was her maid of honour. Misses Bromine and Fluorine
Halide were bridesmaids; little Master Eka-Cacsium was the ring bearer.
Mr. Alkali chosc his best man his brother, Mr. Potassium Alkali.
Messers Lithium, Rubidium, and Caesium Alkali were ushers. The bride
was never lovelier than in her wedding gown of white ccllulosc acetate
which blended perfectly well with her blond beauty. The maid of honour
wore a stccl-bluc-grcy gown of viscose. The bridesmaids were gowned in
reddish-brown and yellow, respectively.
Following the ccrcmony, a reception was held at the Electrolytic Tea
Room for the immediate family. Brine and carbohydrates were served.
The former Miss Chlorinc Halide is a graduate of Anode High School
and Electronic Collcgc, where she was a member of the Beta Ray Society.
240
At present, she is connected with Valence's Mill where she is head
blcaching agent.
Mr. Sodium Alkali is a graduate of Cathodc High School and Cation
College, where he was activc in athlctics, particularly swimming. Mr. Alkali
has travelled extensively on land, sea, and in the air. During the war he
had the honour of serving his country in the Army, Navy, Marine Corps,
and Air Corps. In civilian life the groom holds a prominent position with
the Elcctrochcmical Metallic Company.
After the rcccption the couple left for the Great Salt Lake Region of the
United States where they will make their home among their many friends.
Text 11
The Role of Theory in Chemistry
We start at the beginning and define science as a set of observations
and theories about observations. Wc then define theory as a dcvicc for
making predictions and correlations o f observations. A theory is
composed of axioms, which arc not necessarily self-evident, procedure,
and the output o f the procedure. The axioms identify the system, select
the procedure and its parameters, and interpret its output. Each theory is
judged by the following pragmatic criteria listed in the order o f
decreasing importance.
How diverse is it?
How accuratc is it?
How simple is it?
Like all scicncc, theories evolve; they do so bccausc the basis of our
scicntific knowledge is constantly changing. The best theory at a particular
point in time is the theory that best satisfies the above criteria. It is not to
be judged on a political or a religious basis.
A theory evolves. The axioms arc conccivcd in the mind of the theorist
who also may double as an experimentalist. The output o f the theory arc
predictions and correlations that may suggest new experiments to the
experimentalist. The predictions and correlations arc then compared with
observations. If the agreement between prcdictions-corrclations and
observation is “good” the theory is a “good” theory, which is a pragmatic
value judgement. If the agreement is poor — which occurs sometimes
bccausc new observations have been made — a better theory must be
found by some theorist generating new axioms and a new cycle. This
axiomatic-cum-pragmatic (ACP) cycling is continued until the agreement
between theory and experiment bccomcs “good”. Wc call this proccss
the ACP epistemology o f science bccausc (1) epistemology is the
acquisition and validation o f knowledge and (
2
) wc wish to distinguish
our simplistic view from the more erudite views o f the professional
philosophers.
The ACP epistemology can be applied to areas outside o f scicncc.
241
1 4 , Л I 1 ^
There is a wide variety of chcmical and physical theories from which
wc select as our example theories of matter (atoms, molecules, solids,
nudci, and elementary particles). Wc can illustrate the ACP cpistcmology
with the familiar ball-and-stick theory of molcculcs. This theory employs
sticks and coloured balls with holes drilled in them at prescribed angles.
The procedure consists of assembling the balls and sticks into figures in
all possible ways. The predictions of the theory includc molccular geometry
and the number of isomers cxpcctcd for the moleculc in question. Wc all
feel comfortable with this ball-and-stick theory bccausc it operates in the
three-dimensional, classical world of our senses and seems “real” to us.
While it is a very useful theory, it has a number of significant failures. For
example, it fails to predict both the geometry and the number of isomers
of benzene. More seriously, it fails to predict the clcctronic, vibrational,
and rotational spcctra o f molcculcs. This failure to predict spcctra is
common to all classical theories and has made ncccssary the development
o f a new theory which includes predictive powers in this area. The
nonclassical quantum theory is a theory that predicts more diversely, more
quantitatively, but not more simply than the ball-and-stick theory.
Quantum theory has two essentially equivalent versions: one concerned
with wave mechanics (derived from Schrocdingcr’s work) and one
concerned with matrix mechanics (due to Dirac-Hciscnbcig) which is our
choice. The procedure of the matrix mechanics theory o f matter (MMTM)
is very interesting but is not relevant to the application of the procedure. It
employs vector space and their bases, operators, matrices, secular equations,
eigenvectors, eigenvalues, groups, group algebras, etc., conccpts that arc
well known to mathematicians but essentially unknown, to beginning
physicists and chcmists. In conscqucncc MMTM may seem less “real” to
these beginners than the classical ball-and-stick theory. The MMTM
procedure can be applied uniformly to atoms, molcculcs, solids, nuclci,
and elementary particlcs. It is dear that the conccpt of structure is much
simpler and more intuitive in the ball-and-stick theory than in the MMTM
theory. The MMTM structure concept is that of a set of building blocks
(basis vector o f a vcctor space) that arc assembled under supervision of
the Hamiltonian into a physically significant set of structures (eigenvectors
to the Hamiltonian).
The numerical and algcbraic calculations required in the MMTM
procedure can become quite tedious but fortunately many o f them have
been or can be programmed for personal computers. The calculations of
MMTM then bccomc trivial and operational familiarity is quickly
acquired. Consequently, the challenging part of MMTM bccomcs the
selection o f the vcctor spacc and the Hamiltonian and then the
interpretation of the output.
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title: Theories of Matter - Санкт-петербургского государственного университета высшее профессиональное образование т. А....

text:
In 1926, Sumner made a tremendous advance when he recognized that
enzymes were, in fact, proteins. He came to this conclusion after he had
successfully crystallized a protein
that was associated with enzymatic
activity (viz., urease) and noticcd that the degree of degradation of this
highlypurificd protein could be correlated with the disappearance of the
associated enzymatic activity. Before that time, it was thought that enzymes
might be special nonprotcin substanccs that happened to be associated
with proteins. In other words, it was thought that some proteins might
simply serve as passive, structural supports for enzymes. On the other
hand, Sumner’s discovery suggested that the enzymatic activity was related
to the structure o f the protein per sc. In the 1930s Northrop and Kunitz
purified and crystallized many enzymatic proteins and, thus, confirmed
Sumner as the father of modem cnzymatology.
Text 16
Characteristics of Mossbauer Spectra
To obtain a resonant gamma-ray absorption spcctrum it is ncccssary
to relate the transmission intensity to the instantaneous sourcc-absorbcr
velocity. In practicc there arc a number of methods which can be used to
accomplish this, and these can be roughly divided into two groups: those
which employ constant velocity drives and those which employ
continuously reliable velocity drives. The characteristics and advantages
of cach of these systems have been discusscd in detail by Wcrthcim and
elsewhere. In the present discussion we shall not explore any o f these
methods in detail, but will conccm ourselves only with the details of the
spcctra which arc obtained.
A typical Mossbauer spcctrum is a characteristic plot of the total
number o f events (counts) observed as a function o f sourcc-absorbcr
velocity (the standard convention is to represent motion of the source
toward the absorber by positive velocities and motion of the source away
from the absorber by negative velocities).
The profile of the rcsonancc maximum obeys (ideally) the Lorcntz
relationship:
constant
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title:
/(£)=
ГТ71 - Санкт-петербургского государственного университета высшее профессиональное образование т. А. Степанова,...

text:
Text 17
Free Radicals
An atom or group of atoms with one or more unshared electrons, which
may enter into chcmical-bond formation is callcd a
free radical. (The same
group in a molcculc is callcd a radical; for example the methyl radical in
methyl cyanide or other molcculcs.) Free radicals arc usually highly rcactivc
and difficult to prepare in any except low concentration.
One way of making the methyl radical as a dilute gas is by heating
mercury dimethyl, Hg(CHj)., which decomposes to give metallic mcrcury
and methyl radical. Methyl radical can also be made conveniently by the
decomposition of diacctyl, (CHjCO*)», by cither heat or ultraviolet light.
The diacctyl molcculc liberates two molcculcs of carbon dioxide and two
methyl radicals.
The American chcmist Moses Gombcrg (1866-1947) discovered in
1900 that some hydrocarbon free radicals are stable. He attempted to
synthesize the substancc hcxaphcnylcthanc,
( Q H
j
)
j
C
—C(C
6
Hj)j, which
he cxpcctcd to be a stable, white crystalline substancc. Instead, he obtained
a strongly coloured
solution, with the property of combining readily with
oxygen. He concluded correctly that the solution did not contain the
hcxaphcnyl derivative of ethane, but instead, the free radical triphcny-
Imcthyl, with the formula (QH
3
)jC\ Many similar hydrocarbon free radicals
have been made, and it has been shown that they arc paramagnetic, and
accordingly contain unpaired electrons (the paramagnetism is due to the
magnetic moment o f the clcctron spin o f the unpaired clcctron). The
stability of the triphcnylmcthyl radical, which is responsible for
the low
bond energy of the carbon-carbon bond in the substituted ethane, is
attributed to the resonance energy of the unpaired clcctron among the
various carbon atoms of the molcculc.
Text 18
The Manufacture of Sulphuric Acid
It is a matter of common knowledge among chcmists that sulphuric
acid is made by two processes, the
contact process and the
lead-chamber
process, which arc now about equally important.
In the contact process sulphur trioxidc is made by the catalytic oxidation
of sulphur dioxide (the name of the proccss refers to the fact that reaction
occurs on contact of the gases with the solid catalyst). The catalyst formerly
used was finely divided platinum; it has now been largely replaced by
vanadium pcntoxidc, V:0 }. The gas containing sulphur trioxidc is then
bubbled through sulphuric acid, which absorbs the sulphur trioxidc. Water
is added at the
proper rate, and 98% acid is drawn off.
In the Icad-chambcr proccss oxygen, sulphur dioxide, nitric oxide, and
a small amount of water vapour arc introduced into a large lead-lined
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chambcr. White crystals of nitrosulphuric acid, NOHSO
4
(to put it in
another way, sulphuric acid in which one hydrogen ion is replaced by the
nitronium ion, : N a O*:), arc formed. When steam is introduced the crystals
react to form drops of sulphuric acid, liberating oxides o f nitrogen. In
effect, the oxides of nitrogen serve to catalyze the oxidation of sulphur
dioxide by oxygen. The reactions that occur may be summarized as
2SO:+NO + NOj+ 0 :+ H :0 -> 2N0HS0,;
2
NOHSO
4
+ H :0 -> 2H:S0*+ NO + NO:.
The oxides of nitrogen, NO and N 0 2, that take part in the first reaction,
arc released by the second reaction, and can serve over and over again.
It should be pointed out in conclusion that however widespread these
processes may be, they arc by no means tlic only ways o f the manufacture
of sulphuric acid.
Text 19
W hat Is Light? W hat Is an Electron?
During recent years many people have asked the following questions:
“Docs light
really consist of waves or of particles? Is the clcctron
really a
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text:
particle, or is.it a wave?”
These questions cannot be answered by one o f the two stated
alternatives. Light is the name that wc have given to a part of nature. The
name refers to all of the properties that light has, to all of the phenomena
that are observed in a system containing light.
Some of the properties of light resemble those of waves, and can be
described in terms of a wave length. Other properties of light resemble
those of particles, and can be described in terms o f a light quantum, having
a certain amount of energy, Itv, and a ccrtain mass, /iv/с2. A beam o f light
is neither a sequence of waves nor a stream of particles; it is both.
In the same way, an clcctron is neither a particle nor a wave, in the
ordinary sense. In many ways, the behaviour of clcctrons is similar to that
expected of small spinning particles, with mass— w, clcctric chargc— e,
and ccrtain values o f angular momentum and magnetic moment. But
clcctrons differ from ordinary particles in that they also behave as though
they had wave character, with wavelength given by the dc Broglie equation.
The clcctron, like the proton, has to be described as having the character
both of a particle and of a wave.
After the first period of adjustment to Uicsc new ideas about the nature
o f light and of clcctrons, scientists became accustomcd to them, and found
that they could usually predict when, in a ccrtain experiment, the behaviour
o f a beam o f light would be determined mainly by its wavelength, and
when it would be determined by the energy and mass of the photon; that
is, they would know when it was convenient to consider light as consisting
o f waves, and when to consider it as consisting of particles, the photons.
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Similarly, they learned when to consider an clcctron as a particlc, and
when as a wave. In some experiments the wave charactcr and the particlc
character both contribute significantly, and it is then necessary to carry
out a careful theoretical treatment, using the equation of quantum
mechanics, in order to predict how the light or the clcctron will behave.
Text 20
The Nature of Resonance
The idea of resonance has brought clarity and unity into modem
structural chcmistry, has led to the solution of many problems o f valcncc
theory, and has assisted in the correlation o f the chcmical properties of
substanccs with the information obtained about the structure of their
molcculcs by physical methods.
The goal o f a structure investigation of a system is the description of
the system in terms of simpler entities. This description may be divided
into two parts, the first relating to the material particles or bodies of which
the system is considered to be composed, and the second to the ways in
which these particles or bodies arc interrelated, that is, to their interactions
and interconnections. In describing a system it is usually convenient to
resolve it first into the next simpler parts, rather than into its ultimate
constituents, and then to carry the resolution further and further in steps.
Wc arc thoroughly accustomed to this way of describing the material
constitution of substances. The use of the conccpt of resonance permits
the extension of the procedure to includc the discussion hot only of the
next simpler constituent bodies but also o f their interactions. Thus the
material description o f the benzene molcculc as containing carbon and
hydrogen atoms, which themselves contain electrons and nuclei, is
amplified by use of the resonance conccpt in the following way: The
structure of the normal benzene molcculc corresponds to resonance be tween
the two Kckulc structures, with smaller contributions by other valcncc
bond structures, and the molcculc is stabilized and its other properties are
changed somewhat by this resonance from those expected for either Kckulc
structure alone; cach Kckulc structure consists of a certain distribution of
single and double bonds, with essentially the properties associated with
these bonds in other molcculcs; cach bond represents a type of interaction
between atoms that can be dissolved in terms of the resonance between
structures differing in the interchange of electrons between atomic orbitals.
Text 21
Benjamin Franklin and Electricity
January 17,2006, will be the 300th anniversary of the birth of Franklin.
Kant once remarked that Benjamin Franklin was a new Prometheus
who had stolen fire from heaven. In his own day, Franklin was celebrated
248
throughout all Europe as the world’s foremost electrician and his book on
the subject was in demand in many countries. Far-reaching in its influence,
the book became an important Text in the electrical field and even today
wc still write of electricity in terms introduced in print by Franklin. Used
in the electrical sense, probably for the first time, in the inventor’s book
were words such as armature, battery brush, charged, charging, condense,
conductor, discharge,electrical fire, electrical shock, electrician, electrified,
electrify, Leyden bottle, minus, negative, non-conducting, non-conductor,
non-clcctric, plus, positive, and others.
Franklin saw his first electrical demonstration in Boston in 1746. He
purchased all the apparatus used by the British experimenter, Dr. Spence,
and proceeded in electrical experiments of his own with great interest.
The work that he did was soon far ahead of the European discoveries.
With great enthusiasm, he described new discoveries that were to him
unique, for he had no way of telling what work his predecessors had done.
Foremost among the observations was the discovery of the action of points
in drawing off and throwing off the electrical fire. One of Franklin’s
scicntific achievements was his experiment with the Leyden jar. He
explained the startling discovery that the electrified jar bccamc chargcd
positively on the outside, negatively on the inside, and showed by means
of experiment that the positive charge on the outer coating of the jar was
exactly equal and opposite to the negative inner charge.
Besides the importance and usefulness of Franklin’s discoveries, die
world knows him well for his hypothesis concerning the electrical nature
of lightning. Up to his discoveries the general impression was that lightning
was caused by the explosion of poisonous gases in the air. In 1749, Franklin
established that clcctrical fluid and lightning had similar properties of giving
light, colour of the light, crooked direction, swift motion, being conducted
by metals, crack or noise in exploding, subsisting in water or icc, rending
bodies it passes through, destroying animals, melting metals, firing
inflammable substanccs, sulphureous smell.
Text 22
Future Perspectives
The production of protein from chemicals is not the only proccss one
can employ for converting chemicals to food, but it is representative o f
one major type of proccss: fermentation. Microorganisms arc able to
efficiently producc nutrients, including proteins, fats, carbohydrates,
vitamins, etc., with high productivity. With microorganisms, it is possible
to intensively convert chemicals to food regardless of climatic variation
and environmental pressures. Thus, this route to food production is likely
to increase in both developed and developing countries. The needs o f the
future arc to develop more efficient methods of converting chemicals to
foods and to develop more applications of the final product. This latter
249
point is cspccially important when wc remember that “a food is not a food
until it is eaten”, and it is ncccssary that someone be willing to buy it
before it can be sold. In fact, developments in the area of application arc
likely to be rate-limiting steps in the utilization of these novel foods.
In addition to protein by fermentation, one can make specific products
like essential amino acids (c. g., lysine, tryptophan, and threonine) which
may be used to supplement plant protein sources as a way to increase their
nutritive value. Again, the limitation is frequently in methods of application
and/or economics.
There will continue to be a need to trap our widespread but difficult-
to-usc resources such as coal and oil shale, and to utilize effectively our
renewable resources such as cellulose, as initial starting products for food.
Microorganisms arc quite unique in that they can take a wide variety of
raw materials and sufficiently convert them to foods. In a sense, they
represent miniature farms and factories all in one. The future use of these
organisms to overcome food shortages lies in the hands of the creative
scientist and engineer.
Text 23
Gas Chromatography Methods
Gas chromatography (GC), or, more recently, gas-liquid chro
matography, is based on the volatilization of thermally stable analytes which
have a vapour pressure of approximately
0.1
mm or greater at temperatures
less than 400°C. It is one of die outstanding and more recent methods
which have revolutionized the chcmical analysis of major and minor
components (analytes) for both organic and inorganic analyses. Trace
organic analysis comprises the area of greatest application for gas
chromatography, but there arc several GC techniques available for inorganic
pollutants. Some of the inorganic constituents may be relatively involatilc
and may also be of fairly high molccular weight. Spccial sampling and
processing techniques may be used in such cases, and these includc
pyrolysis, dcrivatization, and the indirect analysis of reaction products. A
promising area for tracc analysis of inorganic constituents involves the
conversion of the tracc element to a chelate compound or organomctallic
and subsequent GC determination using clcctron capture detection. A flame
photometric detector can also be used in GC for metal-containing
compounds. The time required for chcmical analysis using GC is normally
from a few minutes to half an hour. However, for some complex samples,
the time involved in sample separation, quantitative data reduction, and
sample identification can extend for several hours. The accuracy of GC
analysis is governed by the sampling and injection procedures, attainable
resolution, the detectors and dctcctor calibrations, peak area measurements,
and the availability of suitable standards for GC. The precision attainable
depends greatly on the particular analytical chemist’s experience and also
varies for different concentration levels.
250
In rcccnt years, the versatility of GC has been greatly extended by the
so-called ancillary techniques. This refers to the coupling of different
instrumental or chcmical methods with GC in one unified system. Examples
arc the coupling of GC with infrared and Raman spectroscopy, mass
spectrometry, NMR spectroscopy, thin-layer chromatography, microrcactor
systems, and pyrolyzcrs.
Text 24
Liquid Chromatography Detectors
During the last years, there has been a marked increase of interest in
column liquid chromatography (LC). One reason that this technique, whose
discovery preceded gas chromatography (GC) by many years, has not been
used extensively until relatively rcccntly, has been due to the inherent
shortcoming of suitable detection devices to times involved. Promising
improvements in detector design during the last years, however, have made
it possible to use a number of different modes of detection with highspeed,
highcfTicicncy liquid chromatographic columns.
High resolution column LC is a technique which is experimentally
analogous to GC, in that one makes use o f small sample sizes (microlitrc
quantities), long, narrow bore columns, fast moving liquids, and continuous
and highly sensitive detection devices. The term “liquid chromatography”
includes several distinct types of interaction, i. с., ( I) liquid-liquid, in which
the components arc separated by partitioning between a mobile and
stationary liquid; (
2
) liquid-solid, in which the components arc selectively
adsorbed on an activc surfacc; (3) ion exchange, in which ionic
components of the sample are separated by selective exchange with
replaceable ions of the support; (4) permeation, in which separations occur
on a permeable gel by a sieving action based on molccular size.
The advantage of liquid chromatography is that thermally unstable,
nonvolatile compounds which cannot be eluted by GC, can often be
separated by LC, sincc columns arc operated at or near room temperature.
Applications therefore seem feasible for such high molccular weight
compounds as proteins and polymers. Too, the interchange of solvents
can provide special selectivity effects in LC, sincc the relative retention of
two solutes is strongly influenced by the nature of the eluent used. Although
LC is not likely to replace GC as an analytical technique, the two methods
should complement one another.
The current interest in column LC is evidenced by numerous articles
which arc now appearing in the literature. Column liquid chromatography
has been successfully employed by several workers in the analysis of
steroids, hcrbicidcs, insccticidcs, metal organic compounds and biologically
activc materials. Rcccntly, reports have appeared, describing improvement
in performance and efficicncy of LC columns by the development of
controlled surfacc porosity supports and by the use of high speeds and
high pressures, enabling the tcchniquc to bccomc competitive with GC.
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