2018-02-13
2243
Learn the new vocabulary:
| solid | твердий; тверде тіло |
| to be common knowledge | бути загальновідомим |
| for instance | наприклад |
| to melt | танути |
| to evaporate / vapor | випаровуватися / пара |
| to be liquefied | перетворюватися на рідину |
| volume | об’єм, обсяг |
| shape | форма |
| neither … nor … | ні … ні … |
| thorough knowledge | глибокі знання |
| various | різноманітні |
| to be composed (of) | складатися (з) |
| essential | важливий, необхідний |
1. Read and translate the text:
The fact that matter may exist in three physical states (solid, liquid and gas) is common knowledge. It is usually possible to change matter from one state to the other by changing its temperature. For instance, a piece of ice is called a solid; it may melt and form a liquid; as it evaporates, liquid water changes into a vapor, i. e. into the gaseous state.
Many kinds of matter, like water, can be obtained in each of the three states; for some, however, extraordinary means have to be used in order to produce one, or even two of the states; and for others, only two states are known or can be produced.
Common salt, for example, exists normally as a solid; at a temperature of several hundred degrees, it can be liquefied; and at still higher temperature it is converted into vapor. Carbon, a solid under normal conditions, can be vaporized, but it has never been liquefied.
Solids have both a definite volume and a definite shape. Liquids, too, have a definite volume, but they take the shape of their containers.
Gases have neither a definite shape nor a definite volume. A chemist must have a thorough knowledge of the states of matter and of physical laws that govern the behavior of matter in various states.
That all matter is composed of molecules is known to everybody. The question which must be answered, then, is: if all matter is composed of molecules, what is the essential difference between the states of matter? The answer to this question is that the essential difference between these states is the relative quantities of energy molecules possess in different states.
2. Find in the text sentences where the author describes:
1) the facts that are well-known;
2) examples of matter changes;
3) the necessity for a specialist to know matter transformations;
4) a question on the matter composition and the answer to it.
3. Answer the following questions:
1. How is it usually possible to change matter from one state to the other?
2. Can all kinds of matter be obtained in each of the three states?
3. What do solids have?
4. What characterizes gases?
5. Why should a chemist know the states of matter?
6. What other substances besides water can be obtained in the three states?
4. Look through the text and say what information is not necessary to understand the topic.
5. Find the text English equivalents to the given Ukrainian words, word combinations and chemical terms:
| 1. загальновідомо | 12. виробляти |
| 2. звичайно | 13. форма |
| 3. існувати | 14. тверде тіло |
| 4. надзвичайні засоби | 15. випаровуватися |
| 5. танути / плавитися | 16. об’єм |
| 6. градуси | 17. глибокий / ретельний |
| 7. певний | 18. як, аналогічно |
| 8. складатися (з) | 19. випарюватися |
| 9. відносна кількість | 20. вуглевод |
| 10. перетворюватися | 21. ще, все ще |
| 11. отримувати |
6. Match the Ukrainian words, word combinations and chemical terms from ex. 5 with the English equivalents:
| a) to obtain | l) like |
| b) common knowledge | m) usually |
| c) definite | n) carbon |
| d) relative quantity | o) to be composed of |
| e) still | p) extraordinary means |
| f) to melt | q) to vaporize |
| g) to exist | r) degree |
| h) volume | s) to convert |
| i) to evaporate | t) solid |
| j) to produce | u) shape |
| k) thorough |
7. Complete the following sentences using modal verbs:
1. Chemicals... be used carefully in the laboratory.
2. You... stay out of the laboratory if your teacher is not there.
3. You... obey the laboratory rules when working there.
4. If you... to smell any chemical, fill your lungs with air first, then sniff carefully.
5. As you... see, many of the chemicals... be dangerous.
6. All chemicals... to be treated with care.
7. Ethanol and water... look alike.
8. What we... to remember is that a substance... be recognized by its properties.
9. How... you tell that a substance is pure?
10.Dalton's ideas about atom... explain many experimental observations and scientific laws.
11.Elements... be decomposed because the atoms they are made of are indestructible.
12.The question that we... answer at the start is: how do the atoms get electrical charges?
TEXT 8
STATES OF MATTER
Learn the new vocabulary:
| motion | рух |
| to slow down | уповільнюватися |
| to add | додавати |
| to speed up | прискорюватися |
| randomly | у довільному порядку |
| clamp together | з’єднуватися / об’єднуватися разом |
| in many ways | у багато способів |
| to decrease | зменшувати(ся) |
| to store | зберігати |
| in pattern | за моделлю, за зразком |
| dimension | напрямок |
| to be realized | реалізовуватися, утворюватися |
| to probe deeper | глибше досліджувати |
1. Read and translate the text:
Matter can occupy three different states — gas, liquid and solid. Changes of state depend on the motion of sub-microscopic particles. The motion of these particles depends on energy. Cooling particles takes away energy and slows them down. Heating particles adds energy and speeds them up. In a gas these particles move quickly and randomly, they have neither set volume nor shape. In a liquid the particles slow down and clamp together. We use gases, such as a natural gas, in many important ways. Cooling a gas into a liquid decreases its volume dramatically. This makes it possible to store and transport it more effectively. In a solid particles of matter have a definite volume and shape. They are held in a pattern that repeats itself in three dimensions. Crystals are highly ordered form of solid matter. They were one of the first clues to the arrangement of particles in the solid state.
The states of matter are few. But the ways in which they are realized, the number of different substances around us, are many. Let’s see an example. On breathing oxygen — the life-giver — is obviously a gas. But here is another element, sulphur that chemically very closely related to oxygen. And yet, it is obviously different: it is a solid at room temperature. Now, there are obviously different forces that work between the atoms of molecules of sulphur and oxygen within these two substances. We want to know why this is so. We have to probe deeper, we have to, then, ask: What is the nature of the atom? What is it that makes oxygen and sulphur similar or different?
2. Work in pairs and make up a dialogue out of the text below. Act your dialogue in front of your fellow students. There are some possible situations where your dialogue could take place:
1. Two students are discussing the lecture they've just heard.
2. A student discusses his/her paper with the supervisor.
3. At the examination the professor asks the student a few questions on the states of matter, and the student answers.
3. You're given descriptions of ten elements of the Periodic Table. Give the names and symbols of the elements. If in the given definitions some important details are lacking, add whatever you consider necessary. Choose the elements from the list below:
chlorine, tin, hydrogen, zinc, copper, bromine, carbon, helium, silver, oxygen
1. Chemically it is a reactive metal, combining with oxygen and other nonmetals and reacting with dilute acids to release hydrogen.
2. Chemically it is reactive. It combines directly with chlorine and oxygen and displaces hydrogen from dilute acids. It also dissolves in alkalis to form stannates.
3. It is a white lustrous soft metallic transition element. It is used in jewellery, tableware, etc., and its compounds are used in photography.
4. A colorless, odorless gaseous element. It is the most abundant in the Earth's crust (49.2 percent by weight) and is present in the atmosphere (28 percent).
5. A colorless, odorless gaseous chemical element. It is the lightest and the most abundant element in the universe. It is used in the Haber process.
6. This nonmetallic element is totally inert and has no known compounds. It was discovered in the solar spectrum in 1868.
7. It is a red volatile liquid at room temperature. Chemically, it is intermediate in reactivity between chlorine and iodine. The liquid is harmful to human tissues and the vapor irritates the eyes and throat.
8. It is manufactured by the electrolysis of brine and also obtained in the Downs process for making sodium. It has many applications, one of which is purification of drinking water.
9. The name of this element comes from the island of Cyprus. It is used for making electric cables and wires. Its alloys are used extensively. Water does not attack it, but in moist atmospheres it slowly forms a characteristic green surface layer (patina).
10. A nonmetallic element belonging to group IV of the Periodic Table. It has two main allotropic forms (diamond and graphite).
