14. Explain why...

1. Copper is important to our health.

2. Copper is widely used in medicine.

3. The ancient Egyptian plumbing system is still in a serviceable con­dition.

4. Copper cookware is preferred by cooks worldwide.

5. Copper is the standard for electrical conductivity.

6. Aluminium is being replaced with copper in computer chips.

7. Transport means need copper.

8. Copper alloy tools are used in situations where explosions are feared.

9. Copper metals are popular as a decorative material.

10. The Statue of Liberty needed little restoration.

15. Translate the original and derivative words, using a dictionary and create several new words by adding suffixes:

verb	noun (abstract)	noun (personal)	adjective
-	science	scientist	scientific
to found	foundation	founder	-
to classify	classification	-	-
to depend	dependence dependability	dependent	dependent dependable
to predict	prediction	predictor	-
to discover	discovery	-	-
to originate	origination	originator	-
to define	definition	-	definite
to conduct	conductivity conduction conduct	conductress	conductive
to treat	treatment	-	-
to compare	comparison	-	comparable comparative
to design	проект	designer	-

16. Read the text dealing with discovery of metals and opening the Periodic Law.

Metals in Periodic Table

Chemical elements were being studied for a long time in the middle of thе 18^th century. French scientist Lavoisier laid the foundation of the chemical science, having started the quantitative analysis of the elements. Early in the 19^th century English chemist John Dalton tried to establish the atomic theory. By the middle of the 19^th century chemical elements had been classified into two general groups: metals and non-metals.

T he step forward during this period was the idea of new concept called “valence”, which meant the capacity of atoms to combine with one another. Later, it was found that the properties of chemical elements depend on their atomic weight. So, a Russian scientist D. I. Mendeleyev (1834–1907) could build up a periodic classification of all the then known elements. According to his theory, Mendeleyev predicted the properties of some undiscovered elements for which he left blank spaces. The theory became true and in 1875 such elements as gallium was discovered, taking the place below zinc. Scandium was discovered in 1879, filling the gap below calcium and germanium – in 1886, taking the place near gallium, below zinc. In the memory of the originator of the Periodic Law the 101^st element discovered by American scientists in 1951 was named mendeleyevum. Mendeleyev’s Periodic law is regarded to be one of the most recognized and important achievements in science.

D . I. Mendeleyev was not the only Russian scientist dealing with metals. M. V. Lomonosov formulated the first definition of the word “metal” in the following way: “A metal is a bright solid that can be forged”. Besides, the characteristic features of metals are lustre, toughness, workability, electrical and heat conductivity and others. Metals are well processed materials. They can be cast, forged, stamped, extruded, rolled, cut, welded.

It is the presence of iron that divides metals into ferrous and non-ferrous. And it is by this reason that iron may be considered to be the most important element in Periodic Table. The abundance in which iron is founded, its great strength, its remarkable ductility and malleability make it especially suitable for many works where strength with lightness are required. However, in ancient states the use of iron, either cast or wrought, was rather limited, bronze being the favourite metal almost for all purposes. Bronze is known to be the alloy of copper and tin.

Bronze and other non–ferrous metals, such as gold and silver, may be treated in various ways, the chief of which are: casting in mould and treatment by hammering and punching. Along with bronze brass (an alloy of copper and zinc) is widely used because of its cheapness in comparison with bronze. Besides, analyses of the iron of prehistoric weapons showed that they contained a considerable percentage of nickel. And in many specimens of ancient bronze, small quantities of silver, lead and zinc were also found.

It is worth mentioning that both ferrous and non-ferrous metals are widely used in a great variety of works and non-ferrous materials are predominant in works of art. Many metals of Periodic Table can interact with each other and develop quite new materials and alloys. For example, aluminium oxide which is also referred to as corundum, sapphire, ruby or aloxite are mentioned in the mining, ceramic and materials science. Rubies are given their characteristic deep red colour and laser qualities by adding such metallic element as chromium. Sapphires come in different colours given by impurities of iron and titanium. Aluminium oxide is widely used in the fa­brication of superconducting devices, particularly single electron transistors and superconducting quantum interference devices (SQUID).

Such metals as boron and nitrogen form boron nitride known as Borazon. The latter is a crystal created by heating equal quantities of boron and nitrogen at temperatures greater than 1800⁰C (3300 F) at 7 GPa (1 million lbf/in²). Borazon replaced aluminium oxide for grinding hardened steels due to its far superior abrasive properties. Other uses include jewellery designing, glass cutting and laceration of diamonds.