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      1. Read the text and correct the statements that follow. Metals

One basis of classification of the elements groups them into metals and non-metals. It is now 2,000 years since Julius Caesar was stabbed in a small auditorium known as Pompey's Curia and his body cremated in the Roman Forum. Since that time, many changes have taken place, but many things have remained the same. Steel is still the basic material of armaments, although, it is not used in the manufacture of shields and short swords. Gold, silver, and copper are, as 2,000 years ago, the coinage metals. Bronze is still used for objects intended to resist the corrosive action of the atmosphere.

Knowledge of the metals, of course, has increased, greatly since Caesar's day. The Roman world knew, at least, copper, lead, gold, silver, tin, iron, mercury, and zinc (in a copper alloy). To this list, the twentieth-century's man in the street might add aluminium, magnesium, nickel, chromium, cobalt, tungsten, molybdenum, uranium, and one or two others.

The first metals which were used by primitive man were those that are found free in nature to a comparatively large extent. These are gold, silver, and copper. Tin entered the metal picture when someone discovered, probably accidentally, that if it was mixed with copper the resulting substance was harder. So there came into being the alloy that we call bronze, a material which was so important in the ancient world that its name is given to one of the cultural stages in human development. The Bronze Age began in Egypt around 3,000 BC and in Europe some 500 or 1,000 years later.

Since almost no iron exists free in nature, it undoubtedly came into general use somewhat later than those just mentioned. As soon as methods were developed for separating iron from its ores in reasonably large quantities and at fairly low cost, it ceased to be classed as a precious material and began its career as the world's most valuable metal from the standpoint of actual use.

Metals are mostly solids at ordinary temperature and have comparatively high melting points with the exception of mercury. They are for the most part good conductors of heat and electricity. They can be drawn into fine wires and hammered into thin sheets, characteristics that are called ductility and malleability, respectively. An ounce of gold can be drawn into a wire almost 50 miles long or hammered into a sheet that has an area of between 175 and 200 square feet.

From the point of tonnage produced and used, iron is the world's most common metal, followed in turn by copper, zinc, lead and aluminium.

1. Bronze is still the basic material of armaments, although, it is not used in the manufacture of shields and short swords.

2. The Roman world knew, at least, copper, lead, gold, silver, tin, iron, mercury, aluminium and zinc.

3. Non-metals are mostly solids at ordinary temperature and have comparatively high melting points.

4. The Bronze Age began in Europe around 3,000 BC and in Egypt some 500 or 1,000 years later.

5. One basis of classification of the elements groups them into solids and liquids.

6. Gold, silver, and bronze are, as 2,000 years ago, the coinage metals.

7. Iron is still used for objects intended to resist the corrosive action of the atmosphere.

LANGUAGE DEVELOPMENT

4. Match the English phrases with their Ukrainian equivalents:

1. melting point a) основний матеріал

2. ordinary temperature b) низька вартість

3. basic material c) хороший провідник

4. human development d) квадратний фут

5. good conductor e) звичайна температура

6. square foot f) точка плавлення

7. low cost g) людський розвиток

5. Fill in the words from the list below. Use each word only once.

electricity, common, elements, melting, development, large, extent

1. the world's most ….. metal

2. comparatively large …..

3. classification of the ….. groups

4. reasonably ….. quantities

5. comparatively high ….. point

6. good conductors of heat and …..

7. cultural stages in human …..

6. Make up word combinations from the following words, translate them into Ukrainian.

1. basic a) metal

2. corrosive b) temperature

3. valuable c) feet

4. actual d) point

5. ordinary e) action

6. melting f) material

7. square g) use

7. Read the text and fill in the gaps with the words from the list below. Use each word only once:

metal, important, century, obtain, useful, brass, alloys, copper, environment

It is only since the time a man had learnt how to _______ and use metals and their _______, he has been able to adapt his _______ to his needs and desires. The present age is, in fact, the Age of Metals and it is _______ that we should have some acquaintance with these _______ substances. In the ancient times, gold, silver, _______, tin, iron, lead and mercury were known as "The Seven Metals".

One other _______, zinc, has also been known in its role as one of the constituents of the alloy _______. Almost no metals other than these seven or eight were known until the eighteenth _______ and many that we use today, not until the nineteenth.

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