ТОП 10:

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

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.

 

Текст B

ANCIENT ALCHEMY

All the metals seemed mysterious (таинственный) to the ancients. They were terribly afraid (бояться) of them, and especially of iron. And so no are in Greek and Roman times studied the metals. It seems that the alchemists (алхимики) were the first to study the metals. The alchemists were curious (любознательный) 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 (тайн). They usually worked alone. And people said of them that they practiced magic and the black arts (черная магия). The alchemists themselves pretended (сами делали вид) to be in contact with the devil and other evil spirits. They made all kinds of queer (странный) 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.

 

Текст 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 (наоборот), 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

Read and learn the following words. Translate the examples.

to divide – делить

non-metal – неметалл, металлоид

e.g. All the elements in the Mendeleyev's Periodic System are divided into metals and non-metals.

The elements are divided into metals and non-metals according to their physical and chemical properties.

Chemical properties are much more important than physical properties for deciding whether (if) this or that element is a metal or a non-metal.

solid – твердый; твердое тело

liquid – жидкий; жидкость

gas – газ

e.g. Metals and non-metals may be solid and liquid.

All metals are solid except (за исключением) mercury which is liquid.

density – плотность, удельный вес

potassium – калий

sodium – натрий

e.g. Metals have a high density (except potassium and sodium), while non-metals usually have a low density.

malleable – ковкий (= ductile)

e.g. Metals are malleable while solid non-metals are brittle.

temperature – температура

point – точка

melting point (= melting temperature) – точка (температура) плавления

boiling point – точка кипения

to melt – плавить

melting – плавление

to boil – кипеть

boiling – кипение

e.g. Metals have high melting and boiling points while non-metals have low melting and boiling points.

conductor – проводник (тепла и т.д.)

poor сonductor – плохой проводник

to heat – нагревать

heat – тепло, нагрев

e.g. Metals are good conductors of heat and electricity while non-metals are poor conductors of heat and electricity (except graphite (графит) which is a good conductor of electricity).

to draw (drew, drawn) – тянуть, волочить

to draw into wire – вытягивать в проволоку

e.g. Metals are ductile, that is (то-есть) they can be drawn into wire while non-metals cannot be drawn into wire.

salt – соль

oxide – окись

basic оxide – основной окисел

metallic оxide – окисел металлов

acid – кислота

acidic оxide – кислотный окисел (окисел неметаллов)

to react with – реагировать с

to form – формировать, образовывать

form – форма

to form salts (oxides etc.) – образовывать соли (окислы и т.д.)

soluble – растворимый

dilute – разведенный, разбавленный

e.g. Diluteacids reacting with metals form different salts.

ion – ион

positive (negative) ion – положительно (отрицательно) заряженный ион

to liberate – выделять(ся) (о веществах при хим. реакциях)

anode – анод (со знаком –)

cathode – катод (со знаком +)

electrolyses – электролиз

hydrogen – водород

to mould – формовать

to press – прессовать

pressure – давление

 

Match the word or word phrase (left column) and its translation (right column). Write them down in your notebooks.

 

а) существительные:

1) non-metal 2) solid 3) liquid 4) gas 5) density 6) temperature 7) boiling 8) melting 9) conductor 10) heat (heating) 11) electricity 12) salt 13) oxide 14) acid 15) ion 16) anode 17) cathode 18) electrolysis 19) hydrogen 20) form 21) pressure a) водород b) электролиз c) катод d) ион e) окись, окисел f) соль g) проводник h) давление i) твердое тело j) газ k) удельный вес (плотность) l) температура m) кипение n) нагрев, тепло o) кислота p) электричество q) жидкость r) анод s) форма t) неметалл u) плавление

b) прилагательные:

 

1) solid 2) liquid 3) malleable (= ductile) 4) poor conductor 5) basic oxide 6) metallic oxide 7) acidic oxide 8) negative 9) low 10) soluble 11) dilute 12) positive 13) high a) высокий b) низкий c) положительный d) твердый e) разведенный f) растворимый g) плохой проводник h) основной окисел i) окисел металлов j) кислотный окисел k) ковкий l) отрицательный m) жидкий

 

c) глаголы и глагольные сочетания:

 

1) to divide into 2) to form salts 3) to react with 4) to draw into wire 5) to liberate 6) to melt 7) to heat 8) to press 9) to mould a) прессовать b) формовать c) делить(ся) d) образовывать соли e) реагировать с f) выделять(ся) g) вытягивать в проволоку h) плавить i) нагревать

 

Read Text В

 

Text В

METALS AND NON-METALS

There are 105 elements in the Mendeleyev's Periodic System. These elements are divided into two groups: the metals and the non-metals. Here is a table showing the difference (таблица, показывающая различия) between metals and non-metals.

Physical properties of metals:

1. Solid at room temperature (mercury is the only liquid metal).

2. Have a high density (except potassium and sodium).

3. Can be moulded by pressure, that is they are malleable.

4. Have high melting and boiling points.

5. Can be drawn into wire, i.e. (that is) they are ductile.

Physical properties of non-metals:

1. Many are liquids and gases at room temperature.

2. Density is usually low.

3. Solid non-metals are brittle.

4. Have low melting and boiling points.

5. Cannot be drawn into wire.

Chemical properties of metals:

1. Have basic oxides.

2. React with dilute acids forming salts.

3. Form positive ions.

4. Are liberated at the cathode during electrolysis.

Chemical properties of non- metals:

1. Have acidic oxides.

2. Salts of non-metals do not exist.

3. Form negative ions.

4. Are liberated at the anode during electrolysis.

 







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