Some Facts about Chemistry

The science of chemistry deals with substances. Chemistry is the investigation and discussion of the properties of substances.

Common examples of substances are: water, sugar, salt, copper, iron and many others.

Chemists study substances in order to learn as much as they can about their properties and about the reactions that change them into other substances. This knowledge is very important as it can make the world a better place to live in, it can make people happier, it can raise their standard of living.

Chemists discovered many laws, investigated many im­portant phenomena in life. They produced many artificial substances which have valuable properties.

Chemistry has two main aspects: descriptive chemistry, the discovery of chemical facts, and theoretical chemistry, the formulation of theories.

The broad field of chemistry may also be divided in other ways. An important division of chemistry is that into the branches of organic chemistry and inorganic chemistry.

Organic chemistry is the chemistry of the compounds of carbon that occur in plants and animals.

Inorganic chemistry is the chemistry of the compounds of elements other than carbon. Each of these branches of chemistry is in part descriptive and in part theoretical.

LESSON 2

Grammar: The Passive voice. The adverb hardly

Text D.I.Mendeleyev

Ex. 1. Поставте речення в пасивному стані як у зразку:

Model: A. Will you use this solvent in your work? B. No, it has already been used.

1, Will he explain this new method to them? 2. Do you want to find out the melting point of this substance? 3. Will they evaporate this solution? 4. Is he going to translate this article this week?

Ex, 2. знайдіть речення у яких дієслова з закінченням –ed є частиною пасивного стану.

1. They produced many new goods at our plant. 2. This new material was produced at our plant. 3. He carried out his first experiment at the age of 18. 4. Great research work is being carried out by our students. 5. D. I. Mendeleyev formu­lated the Periodic Law. 6. This law opened a new era in chemistry. 7. The articles were translated by our students.. 8. He was appointed professor of the physico-chemical department. 9. All the samples will be carefully examined. 10. The work was presented in time.

Ex, 3 Перекладіть речення

1, There is hardly anybody who doesn't know the proper­ties of oxygen. 2. His work was very hard. 3 . He worked very hard and passed all his exams well. 4. There is hardly any living substance which does not consist of compounds contain­ing oxygen. 5. Though he spoke very slowly I could hardly understand him as my English was very poor at the time. 6. The text was very hard and we could hardly understand it.

Ex. 4 . Поставте речення в пасивному стані як у зразку

Model: They gave her an interesting article. She was given an interesting article.

1. I met them in our Institute yesterday. 2. She offered him this work. 3. They invited her to the meeting. 4. We held the meeting in our hall. 5. The students used some sol­vents for their experiments. 6. He wrote a very good report.

Ex. 5. Перекладіть речення

1. When his experimental work was ready he presented it to his professor. 2. At present potassium nitrite is manufactured widely at the plants. 3. His present work is very interesting, he likes it very much. 4.The Present Tense was explained at the last lesson. 5. All the reports which were presented by our young research workers will be discussed. 6. Who was not present at the last lesson? 7. Hydrogen ions are present in solutions of acids.

Прочитайте текст перекладіть українською мовою

TEXT. D.I. MENDELEYEV

D. I. Mendeleyev, the great Russian chemist, was born in Siberia on February 8, 1834. When seven years old he went to gymnasium at Tobolsk. He studied very hard, he especially liked mathematics, physics and history. At the age of 16 he entered the Pedagogical Institute in St. Petersburg, physico-mathematical department. He graduated from the Institute in 1855 and began to teach chemistry at the Technological In­stitute and then at the University. In 1865 Mendeleyev was granted the Doctor of Science degree for the thesis on the com­bination of alcohol with water. This work was both of great theoretical and practical significance. Soon after that D.I.Mendeleyev was appointed Professor of General Chemistry of St. Petersburg University. Despite lectures and supervision of the laboratory, D. I. Mendeleyev carried on great research work.

Mendeleyev's greatest discovery was the Periodic Law, The Periodic Law suggested by Mendeleyev stated that the properties of the elements were a periodic function of their atomic masses. He presented this work to the Russian Chemical Society. MendeJeyev's Periodic Law opened a new era in the history of chemistry.

Mendeleyev was interested in many branches of science, indeed there is hardly any field of science that was not enriched by his contribution. His numerous works dealt with many subjects: properties of liquids, theories of solutions, the development of the gas law, the use of oil and many others. D. I. Mendeleyev was a great patriot. He did everything for the development and progress of his country.

D. I. Mendeleyev continued his research work to the very last day of his life. He died in 1907.

The world is thankful to Mendeleyev for his great contribution to the world science.

Запам’ятайте слова і словосполучення

great society to die

hard significance to be proud of

especially to be appointed to be interested in

to teach (taught, supervision contribution

taught) to suggest liquid

degree very to continue

thesis

Ex. 6. Дайте відповіді на питання

Model: Was your Institute founded in 1920?

Yes, it was. No, it was not.

Yes. it was founded in 1920. No, it was not founded in

1920.

1. Was the experiment carried out in the analytical la­boratory? 2. Was this article translated into many languages? 3. Was D. I. Mendeleyev appointed Professor of General Chem­istry? 4. Was this substance purified before the experiment?

Ex. 7. Дайте відповіді на питання

1. When was D. I. Mendeleyev born? 2. Where was he born? 3. When did he go to gymnasium? 4. What subjects did he like? 5. What Institute did he enter? 6. Where did he work after the graduation from the Institute? 7. When was he granted the Doctor of Science degree? 8. What was he granted this degree for? 9. What was Mendeleyev's greatest discov­ery? 10. What did he present to the Russian Chemical Society? 11. What other problems was Mendeleyev interested in? 12. What subjects did his numerous works deal with? 13. When did he die?

Ex. 8 Перекажіть текст використовуючи наступний план.

1. D. I. Mendeleyev's childhood.

2. The gymnasium and the Pedagogical Institute.

3. D. I. Mendeieyev's work at the Technological Insti­ tute and at the University.

4. His research work.

5. D. I. Mendeleyev's greatest discovery.

6. D. I. Mendeleyev's greatest contribution to science.

7. D. I. Mendeleyev is a great chemist and patriot.

Ex. 9. Перекладіть речення

1. Physics and chemistry are taught at school. 2. Some of the experiments were carried out in our Institute. 3. . Some of the properties of this substance will be predicted. 4 He was appointed Rector when he was 35 years old. 5 Almost all branches of chemistry and physics will be enriched by this new theory. 7. I was told about that great chemist who devoted his life to chemistry. 8. A new la­boratory will be built in May. 9. The professor was asked many questions after the lecture. 10. He was sent abroad to contin­ue his studies. 11. This problem is dealt with in many textbooks. 12. This article will be presented as soon as we fin­ish it. 13. This problem is being discussed by many scientists both in our country and abroad. 14. Some new results were obtained by a group of research workers. 15. This substance cannot be used, it has many impurities.

Ex. 10 Перекладіть речення

1. He was carrying out his experiments-when I entered the laboratory. 2. The substance was examined under the micro­scope. 3. He was born in Siberia. 4. He was interested in chem­istry when he was a schoolboy, 5. He was sent to Petersburg to continue his studies. 6. This student was present at the lecture. 7. This work was interesting both for him and for his students. 8, He was appointed Professor of Moscow University. 9. His work was devoted to physics, 10. He was not present at the Institute yesterday.

Ex. 11. Відкрийте дужки. Перекладіть речення.

1. Many scientists before D. I. Mendeleyev tried to classify elements (despite, according to) their atomic weights. 2. He worked (hardly, hard) at the new problem. 3. It was (very, the very) important to solve this problem in time. 4. They could (hard, hardly) finish their work without his supervision. 5. Elements with (very, the same) properties are at definite intervals in the Periodic Table. 6. When D. I. Men­deleyev went to gymnasium he was interested (both, both. . . and) in mathematics, physics. 7. Give me (very, the very) book you brought. 8. He was very (interested, interesting) in chemistry from (very, the very) childhood. 9. I like (both, both . . . and) these pictures, 10. One may think that (the very, very) amount of heat which will raise the temperature of one gram of water from 0°C to 1°C will also raise the temperature of the same mass of water from 60°C to 61°C.

Ex. 12. Прочитайте текст передайте його основний зміст

In more than a hundred years of its existence the Periodic Law did not lose ^x its significance. The Periodic Law became the property of all nations, like the works of Newton, Lomo-nosov, Einstein and other great scientists.

The importance of D. I. Mendeleyev's discovery is not limited to chemistry alone. The Periodic Law opened up ² the way to the structure of the atom and its nucleus.

At the time when D. I. Mendeleyev published his Table only 63 elements were known. Now 104 elements are known. Thus the Periodic Law discovered a hundred years ago plays a great part in the development of modern chemistry and physics.

LESSON 3

Grammar: The Passive voice. Different meanings of the word much

Text Some facts about atoms

Ex, 1 Поставте речення в пасивному стані як у зразку

Model I: They asked him to investigate this method. He was asked to investigate this method (by them).

1. They showed us a new laboratory of organic chemistry. 2. I told him the news at once. 3. The teacher gave the stu­dents many interesting books. 4. I shall answer all your questions in two days. 5. They will tell her the results when the work is over.

Model II: They sent for the teacher. The teacher was sent for.

1. Everybody spoke about this new method of production.

2. He looked at this modern machine with great interest. 3.We shall send for the doctor if he feels bad. 4. They always listen to him very attentively.

Ex. 2. Перекладіть речення.

1. The rate of this reaction can be strongly influenced by high temperature. 2. The changes in these parameters during decomposition were followed by a number of other changes. 3.Common salt was acted upon by sulphuric acid and hydrogen chloride was produced. 4. His work in this field can berelied on. 5. They were told about the new discoveries in oil production. 6. The change in colour was followed by the change of other properties. 7. Fermi is looked upon as an outstanding physicist of our time. 8. The results of their investigation can be referred to. 9. I was asked to attend his lecture on chemistry. 10. Liquid solutions will be dealt with in this chapter. 11. The qualitative examination of this compound is followed by the quantitative one

Ex. 3 : Перекладіть речення., звертаючи увагу на слово"much":

1. This experiment is much more tedious and time consum­ing than the first one. 2. That work was much more interest­ing for us though it was more difficult. 3. The solubility of helium is much less than that of nitrogen. 4. It would be noted that as much as 20 per cent of this solvent was used. 5. He worked very much last year and could fulfil as much as 50 per cent of his work. 6. Much attention has been paid to the development of nuclear physics in our country. 7. Much research in the field of atomic structure has been carried out recently. 8. As much as 30 per cent of water was evaporated from this solution upon heating. 9, This new discovery is much spoken about.

Ex. 4 Перекладіть речення., звертаючи увагу на слово"mean"

1. In mechanics, force does not mean strength. 2. Elec­trolysis is a process by which a chemical reaction is carried out by means of the passage of an electric current. 3. This means that all the atoms of any element have the same properties. 4. It is generally possible by suitable means to separate the constituents of solutions. 5. Dissociation means the separa­tion of a molecule into its original constituent atoms. 6. A number of various complicated problems has been solved by means of computers. 7. At any given temperature the mole­cules of gases have the same mean kinetic energy

Прочитайте текст перекладіть українською мовою

TEXT. SOME FACTS ABOUT ATOMS

An atom may be spoken of as the smallest particle of any substance.

If atoms cannot be seen it does not necessarily mean that they do not exist. It indicates that any particles, if present, must be extremely small. There are methods by means of which the sizes of atoms and their arrangement in molecules can be determined. One of these methods uses X-ray diffraction.

Some idea of how small atoms are can be obtained by imagining one million copper atoms (radius=0.13X 10~⁹ m (0.13 nm)}. If these copper atoms are stacked one on top of the other, the pile will be as high as the full stop at the end of this sentence.

In the course of many investigations, chemists came to a conclusion that the atoms of different elements are all made essentially of three simple types of units, which were referred to as protons, neutrons, and electrons.

The following diagram shows us the constituents of the atom:

1. Atoms contain the following structural units

2. 2. The position and numbers of these structural units in an atom is shown below:

Electrons fill the space around the nucleus. Number of electrons=Atomic number.

Very small nucleus. Number of protons = Atomic number. Number of protons + Number

of neutrons — Relative atomic mass

The numbers of electrons, protons, and neutrons in an atom of an element can be calculated if the atomic number and rela­tive atomic mass of the element are known

It was also found that many elements and compounds are composed of small numbers of atoms which are held together in a regular arrangement. These groups of atoms are referred to as molecules. The gas hydrogen, for example, is composed of pairs of hydrogen atoms and each pair is called a molecule and its formula is H₃.

Another example is the compound carbon dioxide which is composed of molecules, the formula is C0₃.