II. Say whether the following statements are true or false. Correct the false statements.

1. In chemistry, the term “ferrous metal” is used informally to refer to a metal that oxidizes or corrodes relatively easily.

2. Examples of base metals include iron, nickel, lead and zinc.

3. The term “ferrous” is derived from the Greek word meaning “containing iron”.

4. Noble metals are metals that are resistant to corrosion or oxidation, unlike most base metals.

5. The demand for precious metals is driven not only by their practical use but also by their role as investments and a store of value.

6. A base metal is a rare metallic chemical element of high economic value.

7. Home electrical systems, for the most part, are wired with silver wire for its good conducting properties.

8. The thermal conductivity of metal is useful for containers to heat materials over a flame.

9. The low reflectivity of some metals is important in the construction of mirrors, including precision astronomical instruments.

III. Answer the questions.

1. Can you enumerate all types of metals? Define them.

2. What did alchemists try to do with base metals in ancient times?

3. What metals are used for coins?

4. Do you know what currency code ISO 4217 means?

5. What metals are better known for their uses in art jewelry, and coinage?

6. What features of metals have led to their frequent use in high-rise building and bridge construction?

7. What is thermal conductivity? What is it useful for?

8. What can you tell about special uses of some metals?

Part III

I. Discuss the following questions in class.

1. What is gold? What do you know about this element?

2. How can we get this metal?

3. What do we use gold for?

II. Read the text, answer the questions.

1. What are the properties of gold?

2. Gold forms the basis for a monetary standard used by the International Monetary Fund, doesn’t it?

3. Is it the most malleable metal in the world?

4. What influences the color of this metal?

Gold

Gold is a chemical element in the periodic table that has the symbol Au (from the Latin aurum) and atomic number 79. A soft, shiny, yellow, dense, malleable, ductile (trivalent and univalent) transition metal, gold does not react with most chemicals but is attacked by chlorine, fluorine and aqua regia. The metal occurs as nuggets or grains in rocks and in alluvial deposits and is one of the coinage metals. For millennia gold has been used as money, a store of value and in jewelry. Modern industrial uses include dentistry and electronics. Gold forms the basis for a monetary standard used by the International Monetary Fund (IMF) and the Bank for International Settlements (BIS). Its ISO currency code is XAU. It is the most malleable and ductile metal known; a single gram can be beaten into a sheet of one square meter, or an ounce into 300 square feet. Gold readily forms alloys with many other metals. These alloys can be produced to increase the hardness or to create exotic colors. Adding copper yields a redder metal, iron blue, aluminum purple, platinum metals white, and natural bismuth together with silver alloys produce black. Native gold contains usually eight to ten per cent silver, but often much more alloys with a silver content over 20% are called electrum. As the amount of silver increases, the color becomes whiter and the specific gravity becomes lower. Gold is a good conductor of heat and electricity, and is not affected by air and most reagents. Heat, moisture, oxygen, and most corrosive agents have very little chemical effect on gold, making it well-suited for use in coins and jewelry; conversely, halogens will chemically alter gold, and aqua regia dissolves it. Here are some amazing facts about this metal. The first one is about the most expensive gold coin in the world. One of the world's rarest and most sought after collector coins, the 1933 Double Eagle, was sold at Sotheby’s auction house in New York on Tuesday 30th July 2002 for the record sum of $7.59 million. The second one is about recycling of gold. Today, at least 15% of annual gold consumption is recycled each year. The next is about the first known piece of gold jewelry In Egypt, gold jewelry and other artifacts have been found in Pharaoh’s tombs dating to around 1500 BC and later. And the last one is about the most famous piece of gold. This has to be the face mask of the boy-king of Egypt (1361-1352 BC), Tutankhamen discovered in his tomb in 1922 by Howard Carter.

III. You have read some amazing facts about this metal. Can you add any other facts? You are welcome to use any source of information (Internet, books etc.).