Read and learn the following words. Translate the examples. Metals and non-metals

METALS AND NON-METALS

LESSON 2

MODERN ALCHEMY

Текст C

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.

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

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