1) , , .
2) , , .
3) () - , , .
4) 1869 (), 50 .
5) , .
6) () , , .
Answer the following questions. Try not to use Text A.
1) Why have metals found such wide application?
2) What properties does stone possess?
3) What properties does rubber possess?
4) How many metals did ancient Romans know?
5) How many metals did Lomonosov know in 1763?
6) Why did Lomonosov exclude antimony and mercury from the list of metals?
7) When did Mendeleyev discover his Periodic System?
8) What was the first scientific definition of metals given by Lomonosov?
9) What two main characteristics does the first scientific definition comprise?
10) How are metals defined in engineering?
11) What is an alloy?
Independent tasks
6. Write down all new words and phrases in your notebooks. Group them into sections: nouns, adjectives, verbs, and phrases. Learn these words and phrases for the next lesson.
Write down the names of metals into your notebook. Learn them.
Read additional texts about metals and retell them in Russian.
B
ANCIENT ALCHEMY
All the metals seemed mysterious () to the ancients. They were terribly afraid () of them, and especially of iron. And so no are in Greek and Roman times studied the metals. It seems that the alchemists () were the first to study the metals. The alchemists were curious () people. We know that during twelfth and thirteenth centuries many alchemists lived and worked in England, France and Germany.
The alchemists surrounded themselves with all sorts of mysteries (). They usually worked alone. And people said of them that they practiced magic and the black arts ( ). The alchemists themselves pretended ( ) to be in contact with the devil and other evil spirits. They made all kinds of queer () experiments. They had two aims: they tried to change base metal into gold, and to find an elixir of life, a drink that would keep people young.
C
MODERN ALCHEMY
Ancient alchemists tried for hundred of years to turn mercury into gold by chemical means. Some men devoted all their lives to this impossible task. Today this classic reaction has been performed in reverse (), not by chemical means but through atomic radiation. Scientists have made mercury from gold with the help of atomic reactor.
Gold decays to mercury when it is bombarded with neutrons. The scientists took 600 grams of pure gold powder and placed it in an atomic reactor for 10 months. Then the gold was taken out and left in a special container for another 2 months, so that all the radioactive material could decay. Then the gold was removed from its container and distilled. Of the 600 grams of gold powder 1 gram of mercury 198 was received. Its value is 3,000 dollars (one gram of gold costs about 2 dollars).
This method is not practical and will not be widely used, but the alchemists of old times can be a little happier in their graves knowing that their task has been accomplished even if in reverse.
LESSON 2
METALS AND NON-METALS
