Unit VI petroleum

I. Language

Exercise 1. Read and memorize the following words :

to vary-мiняти, змiнювати(ся)

grade-сорт, клас

opaque-непрозорий, темний

specific gravity-питома вага

composition-склад

crude oil-сира нафта

unsaturated-ненасичений

sulphur-сiрка

nitrogen-азот

hydrocarbon-вуглеводень

impurity-домiшка

viscosity-в’язкiсть, липкiсть

viscosimeter-вимiрник в’язкостi

resistance-опiр, опiрнiсть

flow-течiя;текти,литися

lubricant-мастильний матерiал

mobile-рухомий, моторний

to increase-збiльшувати

extent-ступiнь, мiра

make-сорт,марка

to refine-очищати

refinery-нафтоочисний завод

Exercise 2. Give the initial form of the words and translate them:

Varies, darker, usually, unsaturated, disagreeable, impurities, influenced, density, different, viscosimeter, responsible, composition.

Exercise 3. Fill in the table the given words.

Noun	Pronoun	Adjective	Verb	Adverb	Preposition

Petroleum, from, gravity, usually, nitrogen, for, certain, disagreeable, crude, this, to vary, odour, by, chemical, higher, measure, with, definition, to flow, at, makes, use, mobile, these, always, different, heavy.

Exercise 4. Form the antonomic pairs.

1.high 1.unusually

2.light 2.disagreeable

3.agreeable 3.to absent

4.usually 4.indefinite

5.to present 5.dark

6.definite 6.to reduce

7.like 7.light

8.heavy 8.low

9.to increase 9.never

10.always 10.unlike

Exercise 5. Find the synonymic pairs.

Petroleum, to change, odour, toughness, to vary, to perform, to determine, oil, viscosity, smell, to carry out, make, to define, grade.

Exercise 6. Translate the following word combinations.

Specific gravity, unsaturated hydrocarbon, disagreeable odour, lubricating oils, agreeable gasoline-like odour, large extent, several standard makes.

Exercise 7. Translate the following sentences. Find the meaning of polysemantic word “like”.

1.She likes an aromatic odour of perfume.

2.The engineer would like to measure the viscosity of oils.

3.Pennsylvania petroleum has agreeable gasoline-like odour.

4.Crude petroleums are very mobile, while others, like Mexican crude, are quite viscid.

II.Reading.

Exercise 8 .Read and translate the text A “Physical properties of petroleum” with a dictionary.

Text A .

Physical properties of petroleum

The colour of petroleum varies from light yellow to red, while some very dark grades are opaque. The higher the specific gravity, the darker the oil.

The nature and composition of crude oil usually determines its odour. Unsaturated hydrocarbons, sulphur and certain nitrogen compounds are responsible for disagreeable odours. Crude petroleum from Russia, Romania and California has an aromatic odour. Pennsylvania petroleum has an agreeable gasoline-like odour. Other oils vary in odour depending on the quantity of light hydrocarbons present in the oil, and of the impurities present. The petroleum from South Texas and Mexico has a strong disagreeable odour, due to hydrogen sulphide and other sulphur compounds. Petroleum is lighter that water. The specific gravity is influenced by physical factors and by the chemical composition of the crude oil. It varies from 0.7684 to 0.992.

The viscosity, or the measure of the resistance to flow, is an important factor with lubricating oils. It is usually stated in terms of the time necessary for a definite volume of oil at a definite temperature to flow through a small opening. The actual work is carried out in an instrument known as a viscosimeter, of which there are several standard makes in use at the present time. Crude petroleums are quite different in viscosity. Some are very mobile, while others, like Mexican crude, are quide viscid. Oils composed of hydrocarbons belonging to the series CnHn/2-2 and CnHn/2-4 are viscous. Heavy petroleum in general is composed to a large extent of these hydrocarbons. The viscosity increases with the density. The viscosity of oils of the same specific gravity, but from different sources, are not always the same. This is due to the difference in chemical composition.