The Structure of Covalent Compounds

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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

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

Text 26 A Liquids and Solutions
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 ga

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