Unit 2 Grammar: 1. Present Indefinite Active.

2.Слова-замінники іменників one/ ones, that/ those

Remember the following words and word combinations:

1. earth [‘ə:θ] 1.excessive [ik’sesiv]

2. vapour [‘vəipə] 2. amount [ə ‘maunt]

3. constituent [kəns’titjuənt] 3. soluble [‘soljubl]

4. occur [ə’kə :] 4. fit [fıt]

5. abundantly [ə’bΛndəntli] 5. pure [‘pjuə]

6. tissue [‘tisju] 6. domestic [do’mestic]

7. dissolved [di’zolvd] 7. salt [so :lt]

8. average [‘ævəridЗ] 8. clay [kleı]

9. sodium [‘soudjәm] 9. sewage [‘sju :idЗ]

10. potassium [pә’tæsjəm] 10. mineral [‘minərəl]

Water

Liquid water covers about three quarters of the earth’s surface. In vapour form., water is also an important constituent of the earth’s atmosphere.

In combined form, water occurs abundantly in minerals such as gypsum. In addition, water occurs in animal and vegetable tissues. It constitutes some 70 per cent of the human body and over 90 per cent of some vegetables.

Natural waters often contain dissolved mineral substances. Thus we have mineral waters in which the total mineral content is significantly above the average. Alkaline waters, for example, contain unusual quantities of sodium, calcium, or potassium bicarbonate. Carbonated waters contain carbon dioxide dissolved under conditions of excessive pressure, either natural or artificial¹. Sulphur water contains large amounts of hydrogen sulphide readily detectable by odour.

Siliceous water contain unusual quantities of silica in soluble from. Rivers, lakes, wells, and springs generally supply water for drinking and domestic purposes. Such water commonly contains salts of calcium, iron, magnesium, potassium, and sodium. Besides, it includes organic matter from falling leaves and twigs, and traces of carbon dioxide, oxygen, nitrogen, ammonia and other gases from the atmosphere. There is also a variety of suspended matter in natural water such as fine particles of clay, sand, microscopic organisms including bacteria, and fragments of vegetation. Waters which have appreciable amounts of dissolved salts are always more acceptable for drinking than those free from solids. At the same time, drinking water must be free from toxic salts, disease-producing organisms, and harmful organic or sewage contamination.

Notes

1. either ... or – чи ...чи, або ... або

Exercises.

Ex.1. Find nouns in the following group of words, point out their suffixes and translate:

Constituent, abundantly, addition, constitute, substance, dissolved, significantly, quantity, unusual, readily, important, readiness, condition, acceptable, soluble nature, excessive, occur, domestic, supplied, organic, variety, microscopic, pressure, contamination, harmful.

Ex.2. Point out negative prefixes and translate the words with and without prefixes:

Unusual, insoluble, unimportant, irrational, imperfect, impure, non-toxic, unnatural, inappreciable, irresponsible, immobile, unacceptable, undetectable, imbalance, inorganic, insignificant, unfit, irregular.

Ex.3. Find the pairs of synonyms in the following group of words and translate them:

Important, ordinary, fit, aim, quantity, illness, substance, significant, average, matter, usual, acceptable, harmful, purpose, mean, amount, injurious, disease.

Ex.4. Find the pairs of antonyms in the following group of words and translate them:

Abundant, artificial, usual, insoluble, readily, contaminated, fine, exclude, always, useful, scarce, soluble, large, harmful, natural, small, unusual, never, hardly, include, coarse, pure.

Ex.5. Ask general questions, give the both possible short answers:

Example: Water occurs in minerals. – Does water occur in minerals? (Yes, it does/ No, it doesn’t)

1. We use water for drinking and domestic purposes.

2. She wants to become a pharmacist.

3. Water contains dissolved mineral substances.

4. Water occurs in animal and vegetable tissues.

5. Scientists distinguish between liquid water, water vapour and combined water.

6. Water constitutes an important part of the earth’s atmosphere.

7. Rivers and wells supply people with potable water.

8. This student knows the history of the Chemical-Technological University.

9. Carbonated water contains carbon dioxide.

10. People use water for various purposes.

Ex.6. Make the following sentences negative:

1. Ice covers three quarters of the earth’s surface.

2. These salts dissolve in water.

3. Now they understand the structure of these molecules.

4. Absolutely pure water occurs everywhere in nature.

5. The first-year students always take part in the research work.

6. Good drinking water contains toxic salts and disease-producing organisms.

7. People use sewage water for domestic purposes.

8. A thermometer helps to determine the amount of salts in water.

9. Water freezes at 100°C.

10. Filters always make contaminated water fit to drink.

Ex.7. Translate the sentences; mind the substitutes of the nouns:

1. Waters which have appreciable amounts of dissolved salts are always more acceptable for drinking than those free from solids.

2. This substance reacts 100 times as fast as the other one.

3. We found new ways of synthesis, the older ones being unsatisfactory.

4. The potentials of carbon und nitrogen increase over that of boron.

Ex.8. Find the English equivalents in the text:

Важлива складова частина земної атмосфери; у зв’язаній формі; крім того; вона складає близько 70 % людського тіла; розчинні мінеральні речовини; загальний вміст мінералів; вище середнього; незвичайна кількість натрію; в умовах надмірного тиску; що легко визначається за запахом; у розчинній формі; питна вода; придатний для пиття; з чим вона входить у контакт; не зустрічається у природі; побутові потреби; зависла речовина; дрібні частини глини і піску; відчутна кількість; прийнятний для пиття; вільний від твердих тіл; у той же час; хвороботворні організми.

Ех.9. Answer the following questions on the text:

1. Is water abundant on earth?

2. In what states of aggregation does water occur in nature?

3. Where does water occur in vapour form?

4. Where does water occur in combined form?

5. What part of the human body does water constitute?

6. What do natural waters often contain?

7. What kinds of mineral water do you know?

8. Does absolutely pure water occur in nature? Why?

9. What water is more acceptable for drinking?

10. What must potable water be free from?

Ex.10. Read the text. Find the definitions of: 1) the solution, 2) solubility. Find and translate everything relating to: a) suspension; b) emulsion; c) types of solutions; d) the extent of solubility of various substances.