Text 26 A Liquids and Solutions - раздел Образование, Part One THE PREDICATE Solids And Gases Represent The Extreme States Of Behaviour Of Molcculcs. The ...
Solids and gases represent the extreme states of behaviour of molcculcs. The liquid state can be thought of as an intermediate condition in which some of the properties found in cither solids or gases arc displayed. Liquids, like gases arc isotropic and flow readily under applied stress, but like solids, they arc dense, relatively incompressible, and have properties that arc largely determined by the nature and strength of intcrmolecular forces. With respect to molecular order, liquids arc substances considered to be intermediate between solids and gases. The fact that liquids arc isotropic tells us immediately that they do not have the extended latticc structure and long-range order of solids. Yet, the density of a liquid is generally only 10% less than that of its solid phase; this must mean that the molecules in a liquid are packcd together with some regularity, and do not exhibit the complete chaos associated with molcculcs in the gas phase.
One of the most important properties of liquids is their ability of acting as solvents. In the first place, liquid solutions provide an extremely convenient means of bringing together carcfully measured amounts of reagents and of allowing them to react in a controlled manner. Second, the nature of the reactions which proceed and the speed at which they occur can be greatly influenced by the properties of the liquid solvent medium. Finally, the physical properties of solutions arc interesting and important, because they can be used to determine molecular weights of dissolved substances and to study the nature and strength of forccs between solvent and solute molcculcs.
One of the most engaging and absorbing features of the study of chcmistry is the attempt to explain the behaviour of bulk matter in terms of molecular properties. Therefore, it is important to outline a molecular picture which will help us to understand and relate phenomena associated with the liquid state.
Words and Word-Combinations to Be Memorized
ability, absorb, bulk, complete, convenient, display, engage, generally, intermediate, intcrmolecular, lattice, a means, outline, reagent, range, with respect to, solute, strength
Ex. 5. Give the Russian equivalents for the following:
I think of, display some properties, dense, intcrmolccular forces, with respect to, immediately, the latticc structure, the long-range order, mean, be packed together, provide a means of, carcfully measured, procccd, findlly, bccausc, the behaviour of bulk matter, outline a picturc, be associated with, the strength of forces
Ex. 6. Give the English equivalents for the following:
поведение молекул, жидкое состояние, либо... либо..., главным образом, порядок расположения молекул, занимать промежуточное положение между, на 10% меньше (больше), плотность жидкости, способность действовать в качестве растворителя, протекать с определенной скоростью, оказывать большое влияние, физичсские свойства растворов, определить атомный вес, растворенное вещество, растворитель, растворимое вещество
Ex. 7. Fill in the blanks with articles where nccessary.
1.... liquid state can be thought of as intermediate condition between ... solids and gases. 2. ... properties of liquids are determined by ... nature and strength of... intcrmolccular forces. 3 density of... liquid is
generally only 10% less than that of... solid. 4. Their ability of acting as ... solvents is one of... most important properties of... liquids. 5. It is important to outline ... molecular picturc of... liquid state.
Ex. 8. Give synonyms for the following:
think of, display, under stress, largely, immediately, little, allow, influence, feature, explain
Ex. 9. Give antonyms for the following:
incompressible, extend, long-range, less, convenient, be influenced by, most important
Ex. 10. Translate the sentences into Russian.
1. One should follow the proceeding reaction very carcfully. 2. Selenium, an clement belonging to the sulphur group, is as much non- metal as metal. 3. Many factors mentioned determine the reaction rate. 4. There is a striking resemblance between some elements. 5. St. Petersburg University has its own publishing house. 6. The boiling point of water is accepted to be 100°C. 7. Some objections were found to the Arrhcnius theory long believed to be true. 8. The most striking thing about hydrogen is its extreme lightness. 9. An acid is defined as a compound or an ion capable of liberating a proton. 10. Two or more atoms having identical nuclear chaigcs but different numbers of Acutrons are said to be isotopes. 11. Ores containing as little as 2 per ccnt or even less of coppcr or nickcl arc worth mining. 12. Bond formation involving
elements toward the middle of the periodic table occurs by the proccss of electron sharing. 13. There are a number of different procedures being used in qualitative analysis. 14. The calculation of hydrogen ion concentration in a solution containing a weak electrolyte is a difficult one for the average student first facing this problem. IS. Sulphur dioxide is more than twice as heavy as air and is one of the most easily liquefied gases known. 16. The term "heat** of combustion refers to the amount of heat liberated per mole of the substancc burned. 17. Many industrial processes depend for their success upon the solubilities of the compounds formed. 18. The system of chcmical symbols now used was proposed by the Swedish chcmist Bcrzelius in 1818. 19. Fluorine, though for a long time known to exist, was not isolated until 1886. 20. There has been, sincc earliest times, an atomic hypothesis thought to be implied by the diffusion and the compressibility of gases on the one hand and by the symmetry of crystalline solids on the other. 21. The question of the composition of air long supposed to be one of the elements was solved only in the 18th ccntury. 22. Dangerous bacteria in drinking water may be killed by small amounts of chlorinc. 23. An clement is represented by ccrtain letters for case in writing. This symbol stands for one atom of the clement. 24. There are numerous methods for demonstrating the spectra of many of the elements. 25. In qualitative analysis there is usually greater difficulty in diagnosing the cations present than in recognizing the anions. 26. In English, wc have the practicc of naming chcmical elements in Greek and Latin. 27. As a rule, there are several ways of preparing an element. 28. Mercury has the property, unusual for a metal, of being a liquid at room temperature. 29. The phenomena likely to arise during the experiment must also be taken into account. 30. The amount of the pure metal ccrtain to be obtained for the ore can be calculated in the following way.
Ex. 11. Translate the sentences into English without using a dictionary.
1. Жидкое состояние, которое, как обычно думают, является промежуточным, проявляет некоторые свойства и твердых всщсств, и газов. 2. Подобно твердым веществам, жидкости являются плотными. 3. Плотность жидкости, как обычно считают, только на 10% меньше плотности твердого вещества. 4. Способность быть растворителем — одно из основных свойств любой жидкости. 5. Представить ссбс молекулярное строение жидкости — одно из важнейших условий понимания природы се свойств.
Ex. 12. Answer the following questions:
1. What arc the main states of matter? 2. What factors determine the properties of liquids? 3. Is there any difference in the density of solids, liquids and gases? 4. Why arc liquids usually thought of as solvents? 5. How can one understand the phenomena associated with the liquid state?
^ Scction II
| Упр. 1. Назовите значения следующих интернациональных слов:
• kinetic, analyse, constantly, collision, observation, botanist, diameter, external, convcction, manifestation, dicrmal, suspend, dctcct, individually, csscncc, cxccutc, energy
Упр. 2. Проверьте, помните ли вы значения следующих слов; если нет, обратитесь к словарю:
substantial, motion, single, neighbour, reveal, tiny, incessant, random, cause, intrinsic, wealth, experience, surround, instant, displace, average
Text 26 В
Прочтите текст про себя (контрольное время чтения — 3,5 минуты). A Kinetic Theory of Liquids
In a liquid, molcculcs arc closc to cach other, and consequently the forccs exerted on one molcculc by its neighbours arc substantial. Thus, the problem of analysing the motion of a single molcculc is exceedingly difficult, for cach is constantly in "collision", subjcct to the forccs for as many as twelve nearest neighbours. What then can wc say about molccular motion in liquids? One of the most revealing observations in this respect was made by the botanist Robert Brown in 1827. Brown discovered that very tiny particles (10"4 cm diameter) suspended in a liquid undergo inccssant randomly directed motion. These motions occur without any apparent external causc such as stirring or convcction, and arc evidently associated with an intrinsic property of all liquids. A wealth of experimental observation has confirmed the idea of this Brownian motion being a direct manifestation of the thermal motion of molcculcs. When it is suspended in a liquid, a very small particlc constantly experiences collisions with all the molcculcs surrounding it. If the particlc is small enough, so few molcculcs will be able to collidc with it, that at any particular instant the number striking it from one side may be different from the number striking it from the other sides; consequently, the particlc will be displaced. Subsequently, another unbalance of collisional forccs may occur, this time displacing the particlc in a different direction. The great majority of these displacements arc so small that they cannot be dctcctcd individually, but the motion which is observed is a result of many of the smaller random displacements. In csscncc, a Brownian particlc is a "molcculc" thought to be large enough to be observable, but small enough to cxccutc observable random thermal motion.
Analysis of the motion of Brownian particles shows that their average kinetic energy is 3/2 kT. Since cach particle is to be considered as one of the molcculcs of the liquid wc can conclude that the average kinetic energy of a molcculc in a liquid is also 3/2 kT — cxactly the same as the kinetic energy of a gaseous molcculc at tfie same temperature.
Упр. 3. Передайте основное содержание текста в нескольких предложениях.
Упр. 4. Какое слово в тексте означает «подвергаться воздействию»?
Упр. 5. Найдите в тексте ответы на следующие вопросы:
1. Почему трудно прослсдить движение одной молекулы жидкости? 2. Как в общем можно охарактеризовать движение молекул жидкости? 3. Как выглядит взаимодействие молекул в жидкости? 4. Как определяется средняя кинетическая энергия молекул жидкости?
Упр. б. Закончите следующие предложения:
1. The molecules in a liquid arc ... 2. To analyse the motion of a single molcculc is difficult bccausc ... 3. Brown discovered ... 4. Brownian motion is causcd ... 5. The average kinetic energy of a molecule in a liquid is ...
Scction Ш
Ex. 1. Make up short dialogues according to the example.
Example: — What's the matter? (What's the trouble?)
— It is cold in this classroom.
— It can't be helped. You'd better go to room 312.
Ex. 2. Respond to the following statements:
1. The molccular motion in a liquid is not easy to describe. 2. Molecules in a liquid arc arranged in a rather orderly manner. 3. The properties of the liquid solvent medium influence the speed of reactions occurring in this medium.
Ex. 3. Give detailed answers to the questions.
1. In what way are liquids and gases alike? 2. In what way do liquids resemble solids? 3. Why are the physical properties of solutions important? 4. What forces act between the molcculcs in a liquid?
Ex. 4. Discuss the following topics:
1. The Liquid State as an Intermediate State Between Solids and Gases.
2. Molccular Motion of Liquids.
3. Properties of Liquids.
Все темы данного раздела:
Fluorine
Fluorine, the lightest of the halogens, is the most rcactivc of all the elements, and it forms compounds with all the elements cxccpt the lighter inert gases. This great reactivity may be attribute
Lesson 10
ГРАММАТИКА: Формы н употребление сослагательного наклонения.
Section I
Ex. 1. Pronounce the following words:
С + e, i,y
M
Text 10 В
Прочтите текст про себя (контрольное время чтения — б минут). Uses of Indium
Indium finds most of its uses as an addition to other materials for the purpose of obtaining more desirable pro
Lesson 11
ГРАММАТИКА: Употребление и перевод глаголов may, might, could, ought в сослагательном наклонении.
Scction I
Ex. 1. Pronounce the following words.
pb
Fascinating Phosphorus
Phosphorus is one of the most interesting of all the elements. Its peculiar property of glowing in the dark places it in a special and rare category. For some unexplained reason, man has always bee
Modifications of Phosphorus
Yellow Phosphorus. Phosphorus may occur in three allotropic forms: yellow, violet, and black. However, the two most common forms arc yellow and red. There can be traccd a difference of opinion as t
Lesson 12
ГРАММАТИКА: Повторение темы «Сказуемое».
Section I
Ex. 1. Pronounce the following words:
Помните, что в многосложных словах ударение часто падает на 3-й слог от конца сло
Chemical Symbols for Representing Compounds
It is a short step from using a symbol for an element to using a formula for a compound. However, it is often forgotten that die very act of writing the formula for a compound assumes the law of co
Weight of У12 atom of carbon 12
can be measured experimentally. Therefore the formula NHj can either refer to one molcculc of ammonia, containing one atom of nitrogen, and three atoms of hydrogen, or, alternatively, to one gram-m
Lesson 13
ГРАММАТИКА: Подлежащее. Существительное в функции подлежащего. Местоимение в функции подлежащего.
Section I
Ex. 1. Practise your pronunciation.
a) period ['pionod], anci
Text 13 A The History of Chemistry
There arc five periods in the history of chemistry. The ancient period comprising the older civilizations of China, India, Greece, and their contemporaries to 350 A. D. developed practical arts as
Text 13 В
Прочтите текст про себя (контрольное время — 4 минуты). New Frontiers in Chemistry
Twenty-first-ccntury chemistry has narrowed into units such as instrumental analysis, biochemistry, chemi
Lesson 14
ГРАММАТИКА: Оборот «именительный падеж с инфинитивом».
Section I
Ex. 1. Practise your pronunciation.
a) thought [0o:t], continuous [kon'tinjoos], surfacc ['s3:fis], argue
Text 14 A The Idea of the Atom
Many times during the coursc of history men believed that the solid matter, of which the different things in the world arc made, was really continuous matter. They thought that if you could look at
Text 14 В
Прочтите текст про себя (контрольное время чтения — 3 минуты). The Atomic Theory of Democritus and Dalton
The Greek philosopher Democritus (about 460-370 B.C.) who had adopted some of his
Lesson 15
ГРАММАТИКА: Некоторые особенности перевода на русский язык оборота «именительный падеж с инфинитивом». Оборот «именительный падеж с причастием, прилагательным, числительным».
Section I
Text 15 A The Atomic Theory
In 180S the English chemist and physicist John Dalton (1766-1844) put forward the hypothesis according to which all substanccs were stated to consist of small particles of matter, of several differ
Text 15 В
Прочтите текст про себя (контрольное время чтения — 3 минуты). The Bohr Theory of the Hydrogen Atom
Most our knowledge of the electronic structure of atoms has been obtained by the study o
Lesson 16
ГРАММАТИКА: Инфинитив и инфннитивный оборот в функции подлежащего.
Section I
Ex. 1. Practise your pronunciation.
a) molcculc ["mohkju:!], peculiar [pi'kjuiho], rear
Text 16 A Molecules
To the modern chcmist, the atom is the smallest particle of an clement that can enter into a chcmical reaction. Thus, each clement has atoms that are peculiar to itself and different from those of
Molecular Composition and Size
Molecules are chemical units composed of one or more atoms. The simplest molecules contain one atom each; for example, helium atoms (one atom per molecule) arc identical with helium molccules. Oxyg
I Section I
Ex. 1. Practise your pronunciation.
a) equal ['i.kwolj, pressure ['prcjo], consequence ['konsikwons], gaseous ['gasidsj, weight [weit], cohesion [кэо'Ы.зэп], adjacent [o'dseisont], average
Text 17 A Molecules in Gases and Liquids
According to Avogadro's principle, equal volumes of gases regardless of composition, contain the same number of molccules at the same temperature and pressure. As a consequence of the principle, th
Lesson 18
ГРАММАТИКА: Придаточное предложение в функции подлежащего.
Scction I
Ex. 1. Practise your pronunciation.
a) iodine faiodirn], equilibrium [ ,i:kwi'libnom], fluidity [flu'
Text 18 A The Nature of a Liquid
When iodine crystals arc heated to 114°C, they melt forming liquid iodine. The temperature at which the crystals and the liquid arc in equilibrium — that is, at which crystals have no tendency to m
Text 18 В
Прочтите текст про себя (контрольное время чтения — 3 минуты). The Nature of a Gas
That the molcculcs of a gas arc not held together, but arc moving freely in a volume rather large compare
Lesson 19
ГРАММАТИКА: Место дополнения в предложении. Существительное и местоимение в функции дополнения.
Section I
Ex. 1. Practise your pronunciation.
a) originally [o'ridsonoh],
The Study of the Structure of Molecules
The study of the structure of molcculcs was originally earned on by chemists using methods of investigation that were essentially chcmical in nature, relating to the chemical composition of a subst
Lesson 20
ГРАММАТИКА: Инфинитив и инфинитивный оборот в функции дополнения.
Section I
Ex. 1. Practise your pronunciation.
a) covalent [koo'veilont], distribute [dis'tribjot], elec
The Structure of Covalent Compounds
The clcctronic structure of molcculcs of covalcnt compounds involving the principal groups of the periodic table can usually be written by counting the number of valcncc electrons in the molcculc a
Covalcncc
Many compound substanccs do not have particularly high melting and boiling points, do not conduct electricity when they arc molten, and, thus, give no indication of being ionic. The particlcs of su
Lesson 21
* ГРАММАТИКА: Причастный оборот в функции дополнения.
Section I
Ex. 1. Practise your pronunciation.
a) require [n'kwaid], completion [kom'pli'Jon], extremely (iks'tri:mh]
Factors Influencing the Rate of Reactions
Eveiy chemical reaction requires some time for its complctiQn, but some reactions arc very fast and some arc very slow. Reactions between ions in solution without changc in oxidation state arc usua
A Catalyst
A catalyst is a substancc that alters the speed of a chcmical reaction without itself undergoing any chcmical change, usually only a small quantity of it is required.
Catalysts arc usually
Lesson 22
ГРАММАТИКА: Герундий и герундиальный оборот в функции дополнения.
Section I
Ex. 1. Practise your pronunciation.
a) determine [df t3:min]f prevail [pn'veil], co
Text 22 A Factors Affecting the Boiling Point
The temperature at which a liquid boils, is dependent not only upon the nature of the liquid itself, but also upon the pressure prevailing at the time the boiling point is determined. An increase i
Text 22 В
Прочтите текст про себя (контрольное время чтения—4,5 минуты). Temperature Scales
If two objects are placed in contact with one another, thermal energy may flow from one objcct to the othe
Lesson 23
ГРАММАТИКА: Придаточное предложение в функции дополнения.
Section I
Ex. 1. Practise your pronunciation.
a) measure ['тезэ], centigrade ['scntigrcid], advance [od'va:ns],
Text 23 A Celsius versus Centigrade
The Ninth General Conference on Weights and Measures, held in October, 1948, adopted the name "Celsius" for the scalc of temperature which had more commonly been callcd "ccntigradc&q
The Kelvin Temperature Scale and Modern Means of Measuring the Temperature
About 200 years ago scientists noticed that a sample of gas that is coolcd decreases in volume in a regular way, and they saw that if the volume were to continue to dccrcasc in the same way, it wou
Gas Thermometer
The establishment of the International Temperature Scalc has required that the thermodynamic temperatures of the fixed points be determined with as much accuracy as possible. For this purpose a dcv
Lesson 24
ГРАММАТИКА: Повторение тем «Подлежащее» и «Дополнение»
Section I
Ex. 1. Practise your pronunciation.
a) recognize ['rckognaiz], relative ['relotiv], carefully ['kcofuli],
The Composition and Structure of Water
Water was thought by the ancients to be an clement. Henry Cavendish in 1781 showed that water is formed when hydrogen is burned in air, and Lavoisier first recognized that water is a compound of th
Lesson 25
ГРАММАТИКА: Определение. Прилагательное, местоимение, существительное, наречие в функции определения.
Scction I
Ex. 1. Practise your reading.
The subject of acids and ba
Text 25 A Bases
The subject of acids and bases has long been one of the most controversial in chcmistry, and led to the development of an interesting series of theories.
In the 17th century, during t
The Arrhenius Theory of Acids and Bases
There is perhaps no other class of equilibria as important as that involving acids and bases. As wc continue the study of chcmistry, wc shall find that the classification "acid-base reaction&q
Lesson 26
ГРАММАТИКА: Герундий и герундиальный оборот в функции определения. Причастие и причастный оборот в функции определения. Инфинитив после причастия II и слов likely, sure, certain.
Section
Lesson 27
ГРАММАТИКА: Инфинитив и инфинитивный оборот в функции определения. Придаточное предложение в функции определения.
Section I
Ex. 1. Practise your reading.
It is often tr
Text 27 A The Properties of Solutions
It is difficult to give a definition which tells clcarly and briefly how <r solutions differ from mixtures and compounds, in spite of the fact that solutions arc among the most familiar substanc
Text 27 В
Прочтите текст про себя (контрольное время чтения — 3 минуты). Types of Solutions
Just as the variables, pressure, volume, and temperature, were used to describe the state or condition of
Lesson 28
ГРАММАТИКА: Обстоятельство. Существительное, наречие, герундий и герундиальный оборот в функции обстоятельства.
Section I
Ex. 1. Practise your reading.
As long ago as 183
Interactions in Electrolyte Solutions
In a solution of an electrolyte, it is often ncccssary to have a detailed knowledge of the spccics present. New ions or uncharged molcculcs resulting from interactions in the solution may behave qu
Text 28 В
Прочтите текст про себя (контрольное время чтения—3,5 минуты). Ionic Theories
About the mid-1880's, Arrhcnius postulated in his ionization theory that (1) electrolytes arc completely disso
Lesson 29
ГРАММАТИКА: Причастие и причастный оборот в функции обстоятельства. Независимый причастный оборот.
Section I
Ex. 1. Practise your reading.
The temperature remaining cons
Text 29 A Liquid-Vapour Equilibrium
A liquid of relatively low boiling temperature, when placed in a container open to the atmosphere, will eventually evaporate entirely. Remembering that molcculcs in the liquid arc "bound&
Temperature Dependence of Vapour Equilibrium
Experimental measurements show that the equilibrium vapour pressure of a liquid increases as the temperature increases. In the temperature range in which the vapour pressure is small, it is relativ
Lesson 30
ГРАММАТИКА: Инфишпив и инфинитивный оборот в функции обстоятельства. Придаточные обстоятельственные предложения.
Section I
Ex. 1. Practise your reading.
It is a matter o
Text 30 A Solubility
While there arc many pairs of substanccs which, like water and tfthyl alcohol, can be mixed in any proportions to form homogeneous solutions, it is a matter of common experience that the capacity o
Nonideal Solutions
Consider a solid substancc dissolving in a liquid solvent. The solid is such that when melted, it is converted to a liquid that, in turn, can form an ideal solution with the solvent. The dissolutio
Lesson 31
ГРАММАТИКА: Вводные члены предложения. Инфинитив и причастие в функции вводного члена предложения.
Section I
Ex. 1. Practise your reading.
The terms "oxidation"
Text 31 A Oxidation and Reduction
Generally speaking, the simple meanings of these terms arc that oxidation is the addition of oxygen to a substancc and reduction is the
removal of oxygen. Needless to say, hydrogen se
Text 31 В
Прочтите текст про себя (контрольное время чтения — 3 минуты). Original Meanings of Oxidation and Reduction
Prior to the discovery of oxygen independently by Scheclc of Sweden in 1771-1772
Lesson 32
ГРАММАТИКА: Эмфатические конструкции. Усилительное do. Эмфатические конструкции типа It is... that...
Scction I
Ex. 1. Practise your reading.
It was largely analytical c
Analytical Chemistry — the Oldest Field of Chemistry
Analytical chcmistiy 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 fall
Two Branches of Analytical Chemistry
The relatively small chcmical manufacturing plants producing such chcmicals as alkalis, sulphuric acid, ctc., indeed, some of the factories making consumer goods and employing chcmicals in the proc
Lesson 33
ГРАММАТИКА: Эмфатические уступительные предложения.
Section I
Ex. 1. Practise your reading.
Gradually, chemists began synthesizing some things found in nature and later t
Text 33 A Classical Methods of Analysis
Strange as it may seem now, the analyst and the "works chemist" of the 18th and 19th ccnturics depended almost entirely on what arc frequently defined today as the classical methods of an
Text 33 В Modern Methods of Analysis
Прочтите следующий текст про себя (контрольное время чтения — 3 минуты).
The so-called classical gravimetric and volumctric methods have by no means been superseded by physical chcmistry a
Lesson 34
ГРАММАТИКА: Различные случаи инверсии.
Scction I
Ex. 1. Practise your reading.
Used in the design and interpretation of chcmical experimentation are various statistical m
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 scientific judgement; they rather
Lesson 35
ГРАММАТИКА: Предложения с парным союзом the... the... . Двойное отрицание.
Scction I
Ex. 1. Practise your reading.
When a solid is heated to incandescence, it emits more
Text 35 A Investigations of Spectra
The more profound is the investigation of the structure of atoms and molcculcs, the more problems arise. It was not long ago that consideration of the cxtra-nuclcar clcctrons was rcstrictcd to
Text 35 В
Прочтите текст про себя (контрольное время чтения — 3 минуты). Who Is the Discoverer of Spectrum Analysis?
The more detailed is the scrutiny of the history of chcmistry, the greater is the
Lesson 36
ГРАММАТИКА: Обшсе повторение.
Section I
Ex. 1. Practise your reading.
The guiding light of theory must be confirmed by the bench of physical manipulation.
Ex. 2.
Lesson 36
ГРАММАТИКА: Обшсе повторение.
Section I
Ex. 1. Practise your reading.
The guiding light of theory must be confirmed by the bench of physical manipulation.
Ex. 2.
Why Study Chemistry?
Certainly, the student who has had one year of chcmistry remembers virtually no detail after a few months. The things that stick will generally include some notion of atomic structure, and this inf
Conductance and Electrolysis
Generally speaking, the classification of a substance as a non-clcctrolytc or as an clcctrolytc is based on the conductance of its aqueous solution. Aqueous solutions of non-clcctrolytcs do not con
Text 2 Library and You
Because 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
Text 3 Infrared Spectroscopy
Infrared spectroscopy resembles Raman spectroscopy in that it provides information on the vibrational and rotational energy levels of a spccics, but it differs from the latter technique in that it
Nuclear Magnetic Resonance
The nuclei of atoms can be likened in some respects to. elementary magnets. In a strong magnetic field, the different orientations that the elementary magnets assume correspond to different energie
Text 5 Gold
Perhaps no other metal has played such an important part in the destiny of man as gold has. For ccnturics, it has stood as a barometer of wealth and nobility. To secure it, men have fought, suffere
Text 6 Actinium
Radioactive transition metal of 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 isotop
Radiation Effects on Polymers
Radiation exerts two opposing cffccts 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 cach of the tw
Radiation Effects on Polymers
Radiation exerts two opposing cffccts 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 cach of the tw
Insulator Itirns into Superconductor
Having used ultrahigh pressures and critically low temperatures, scientists at the Institute of High Pressures of the USSR Academy of Sciences have managed to cffcct such a unique transformation as
Text 10 Salt Shaker Wedding
On Friday evening, April 13, at five o'clock, Miss Chlorinc Halidc became the bride of Mr. Sodium Alkali in a double beaker ccrcmony at the Little Church of Mother Nature. Rev. Elcctro Valcncc perf
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 device for making predictions and correlations of observations. A t
Theories of Matter
There is a wide varicly of chcmical and physical theories from which wc select as our example theories of matter (atoms, molcculcs, solids, nuclei, and elementary particles). Wc can illustrate the
Molecular Theory
Matrix mechanics theory of matter (MMTM) is a better molecular theory than the ball-and-stick molccular theory. In thcal> initio MMTM molecular theory the only parameters required by the procedu
Differentiating between Primary, Secondary, and Tertiary Alcohols
A primary or secondary aliphatic alcohol dissolved in pure glacial acetic acid decolourizes a water solution of KMnO*, while a tertiary alcohol fails to do so. A secondary alcohol will continue to
A Brief History of Polypeptide Chemistry
Protein chcmistry really began in the 1830s with Mulder's systematic investigation of nitrogenous biological materials, such as blood fibrin, egg white, gelatins, and silk. In 1840, Huncfeld was th
Characteristics of Mossbauer Spectra
To obtain a resonant gamma-ray absorption spectrum it is ncccssary to relate the transmission intensity to the instantaneous source-absorber velocity. In practice there arc a number of methods whic
Text 17 Free Radicals
An atom or group of atoms with one or more unshared electrons, which may enter into chemical-bond formation is callcd a free radical. (The same group in a molcculc is called a radical; for example
The Manufacture of Sulphuric Acid
It is a matter of common knowledge among chemists that sulphuric acid is made by two processes, the contact proccss and the lead-chamber proccss, which arc now about equally important.
In
What Is Light? What Is an Electron?
During rcccnt years many people have asked the following questions: "Docs light really consist of waves or of particles? Is the electron really a particlc, or is.it a wave?"
Thes
Text 20 The Nature of Resonance
The idea of resonance has brought clarity and unity into modern structural chcmistry, has led to the solution of many problems of valence theory, and has assisted in the correlation of the chcmical
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, Fra
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 of one major type of proccss: fermentation. Microorganisms
Gas Chromatography Methods
Gas chromatography (GC), or, more recently, gas-liquid chromatography, is based on the volatilization of thermally stable analytcs which have a vapour pressure of approximately 0.1 mm or greater a
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 ye
Miscellaneous Grammar
Translate the sentences into Russian.
1. The work referred to also brought to light many examples of abnormal behaviour. 2. Having examined it carefully, wc found out that the gas under in
Words a Student Should Know before Studying the Textbook
a[10]
about* above active after
afternoon
in the afternoon again against ago agree all* alo
Struggle
student
study
suit
summer
in summer sun
Sunday supper swim
table take
take part in tea teach teacher tell ten tenth
that* (th
Chemical Elements
Ac
actinium
(rck'tiniom)
актиний
Ag
silver
j'sdvoj
серебро
Word-building
В английском языке словопроизводство (derivation), т. е. образование одного слова из другого, является самым распространенным способом образования слов.
Образование одного слова из другог
Общие схемы образования производных слов
{ Г"
anion cation
I i
ion
an
Irregular Verbs
arise
arose
arisen
возникать
be
was, were
been
быть, являться; находиться
Новости и инфо для студентов