Lesson 2

Lesson 1

Water

1. Mind the pronunciation of the words below.

standard ['stxndqd], temperature ['tempritSq], laboratory [lq'bOrqtri], atmosphere ['xtmqsfiq], crystal [kristl], ionize ['aIqnaIz], agent ['eIGqnt], combine [kqm'baIn], substance ['sAbstqns], universal ["jHnI'vWsl], hydrate ['haIdreIt], oxide ['OksaId], catalyst ['kxtqlIst], ordinary ['LdInqrI], capillary [kq'pilqri], characteristics ["kxrqktq'rIstiks], accumulate [q'kjHmjuleit], reservoir ['rezqvwR], period ['pIqrIqd], super ['sjHpq].

2. Remember the following words and word combinations.

pure – чистый

layer – слой

considerable – значительный

pressure – давление

mercury – ртуть

freezing point – точка замерзания

boiling point – точка кипения

density – плотность

solid – 1) твёрдый; 2) твёрдое тело

liquid – 1) жидкий 2) жидкость

state – 1) состояние; 2) штат, государство

disturb – нарушать покой, потревожить

lower – понижать

solvent - растворитель

soluble – растворимый

acid - кислота

matter – 1) вещество, материя 2) дело, вопрос

glacier – ледник

measure – измерять

relative – относительный

humidity – влажность

soil - почва

moisture – влага

bound water – связанная вода

differ (from) – отличаться от

spring – родник, ключ

stream – река

drought [draut]– засуха

3. Watch out!

combine – соединять(ся), а не комбинировать

ordinary – обычный, а не ординарный

actually – фактический, а не актуальный

characteristics – свойства, а не характеристика

accumulate – накапливать(ся), собирать(ся), не только аккумулировать

super – сверх, сильно, очень

4. Remember the following linking words and prepositions:

however – однако

like – подобно

because –так как, потому что

as – в виде, в качестве, как

5. Text.

Pure water is an odorless, tasteless liquid. It has a bluish tint, which may be detected, however, only in layers of considerable depth. Under standard atmospheric pressure (760 mm of mercury) the freezing point of water is 0° C (32° F) and its boiling point is 100° C (212° F). Water attains its maximum density at a temperature of 4° C (39° F) and expands upon freezing. Like most other liquids, water can exist in a super cooled state; that is, it may remain a liquid although its temperature is below its freezing point. Water can easily be cooled to about -25° C (-13° F) without freezing, either under laboratory conditions or in the atmosphere itself. Super cooled water will freeze if it is disturbed, if the temperature is lowered further, or if an ice crystal or other particle is added to it.

Water is one of the best-known ionizing agents. Because most substances are somewhat soluble in water, it is often called the universal solvent. Water combines with certain salts to form hydrates. It reacts with metal oxides to form acids. It acts as a catalyst in many important chemical reactions.

Water is the only substance that occurs at ordinary temperatures in all three states of matter, that is, as a solid, a liquid, and a gas. As a solid, or ice, it is found as glaciers and ice caps, on water surfaces in winter, as snow, hail, and frost, and as clouds formed of ice crystals. It occurs in the liquid state as rain clouds formed of water droplets, and on vegetation as dew; in addition, it covers three-quarters of the surface of the earth in the form of swamps, lakes, rivers, and oceans. As gas, or water vapor, it occurs as fog, steam, and clouds. Atmospheric vapor is measured in terms of relative humidity, which is the ratio of the quantity of vapor actually present to the greatest amount possible at a given temperature.

Water occurs as moisture in the upper portion of the soil profile, in which it is held by capillary action to the particles of soil. In this state, it is called bound water and its characteristics differ from free water. Under the influence of gravity, water accumulates in rock interstices beneath the surface of the earth as a vast groundwater reservoir supplying wells and springs and sustaining the flow of some streams during periods of drought.

Notes:

1. 100⁰ C – one hundred degrees Celsius ['selsiqs]

2. 32⁰ F – thirty-two degrees Fahrenheit ['fxrqnhait]

3. either … or – или … или

4. in terms of – в параметрах, в значениях

6. Make adjectives as shown. Translate them.

A. Model: blue – голубой; bluish - голубоватый

green, red, yellow, grey, black

B. Model: colour – цвет; colourless - безцветный

odour, taste, rest, care, motion.

7. Find synonyms:

amount, pure, substance, clean, under, quantity, matter, condition, occur, river, but, state, to be found, stream, collect, characteristic, beneath, accumulate, interstice, reservoir, property, water body, pore, in fact, odour, actually, smell, however, lower, ordinary, decrease, normal.

8. Answer the questions according to the text.

1. What does pure water look like? 2. What are the freezing and boiling points of water? 3. When will super cooled water freeze? 4.Why is water called universal solvent? 5. Water exists in three states? What are they? 6. Give examples of all the three states of water? 7. What is relative humidity? 8. How is water held in the soil? 9. Where does groundwater accumulate? 10. How much of the earth’s surface is covered by water?

9. Retell the text according to the plan:

1. Physical properties of water.

2. Different functions of water.

3. The three states of water.

4. Soil moisture.

10. Some water facts.

Do you know that:

A quarter of the world’s population is without safe drinking water.

Less than 1% of the water treated by public water systems is used for drinking and cooking.

Water makes up 75% of the human brain. 75% of trees are also made from water!

Water expands by 9% when it freezes, making it less dense, which is why ice floats on water.

You could live for a month without food, but you would be dead after a week without water!

Once it evaporates, a water molecule spends around ten days in the air.

97% of the world’s water is salty or otherwise undrinkable, 2% is stored in glaciers and the ice caps, and the remaining 1% is left for humanity's needs.

11. Translate the following text in the written form.

Water is the major constituent of living matter. From 50 to 90 percent of the weight of living organisms is water. Protoplasm, the basic material of living cells, consists of a water solution of fats, carbohydrates, proteins, salts, and similar chemicals. Water acts as a solvent, transporting, combining, and chemically breaking down these substances. Blood in animals and sap in plants consist largely of water and serve to transport food and remove waste material. Water also plays a key role in the metabolic breakdown of such essential molecules as proteins and carbohydrates. This process, called hydrolysis, goes on continually in living cells.

Lesson 2

Дата добавления: 2015-07-14