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Lesson 12
ГРАММАТИКА: Повторение темы «Сказуемое».
Section I
Ex. 1. Pronounce the following words:
Помните, что в многосложных словах ударение часто падает на 3-й слог от конца слова, а ударные гласные читаются кратко, даже в открытом слоге.
a) element ['elimont], significance [sig'nifikans], different [*dif(3)ront], phys ical [Tizikdl], molecular [ma'lekjub], evidence ('evidans], excercise feksasaiz], definite ['dcfinit], experiment [iks'perimont], ncccssary [’ncsoson]
symbol, atomic, case, simple, changc, exhibit, state, rubber, oxygen, show, three, only, pair, inert, avoid, written, also, catch, fire, while, since, way, how, thus, cause, news, world, truly, allow, place, cold, blue, line, pure
introduce [.intro-dju:s], acquire [D'kwaio], quantitative ['kwontitativ], either ['aids], neither ['naido], allotropy [a'lDtropi], rather [*га:дэ]
Ex. 2. Read the following words and say what Russian words help to understand their meaning:
symbol, publish, extraction, Latin, allotropy, molccular, metallic, associate, pair, inert, confusion, temperature, stable, combine, atom, clement, modem
Ex. 3. Pay attention to the following way of word-building:
pre- -t- основа слова — придаст значение «до», «перед», «заранее» prehistoric, prewar, pre-establish, premature, predetermine
post- + основа слова — придаст значение «после» post-war, postposition, postgraduate
(приставка) + основа + основа + (суффикс)
airplane, seawater, electromotive, clcctroncgativity, shorthand, sidestep, sightseeing, old-time, manmadc, lifetime, diclcctropositive
Ex. 4. Find the meaning of the following words in a dictionary. If there is no word in your dictionary, find its parts and derive the meaning yourself.
old-fashioned, sidestep, sightsee, furthermore, water-like, therefrom, up-to-date, electropositive, electrostatic, water-proof, oxygen-rich
Ex. 5. Define what part of speech the italicized words belong to.
1. On account of their inactivity inert gases are often referred to noble gases. 2. Some chcmical phenomena arc not easily accounted for.
Symbols began as a simple shorthand for the names of the elements.
Polonium was named in honour of Poland, the birthcountry of Marie Sklodowska-Curic. 5. At temperature below 0°C, water turns solid. 6. Some solids practically do not dissolve.
Text 12 A
Chemical Symbols for Elements
The Swedish chcmist Berzelius (1779-1848) introduced the modem symbols for the elements when he published a list of “atomic weights" in 1818. Those elements which, on account of their case of extraction from their ores had been known from prehistoric times, were given symbols derived from their Latin names.
The symbols began as a simple shorthand for referring to the names of the elements, but rapidly acquired a quantitative significance. Pb began meaning “some lead”, but it rapidly changed and came to mean cither “one atom of lead” or “one gram atomic weight of lead”, i. e. 207 g of lead.
Some elements can exhibit allotropy; that is to say, they can exist in two different forms in the same physical state. Taking examples from among gaseous elements, ozone and molecular oxygen both contain only oxygen atoms, yet, the reactions of ozone arc completely different from those of oxygen. It will immediately oxidize rubber and metallic silver, whereas oxygen will do neither. Evidence from gas-volume determinations shows that three atoms of oxygen arc associated in ozone, whereas there arc only two atoms in molecular oxygen. The atoms of all common gaseous elements exist in pairs except the inert gases. To avoid confusion, molecular gases are written 0>, N2, Cl> and ozone Oj.
Some elements also exhibit allotropy; for example, white phosphorus catches fire in air at room temperature while red phosphorus is stable in air at 240°C. But since there is no way of discovering how many atoms arc combined together in any solid, the question is sidestepped, and all solid elements including allotropcs arc given symbols; thus, both white and red phosphorus arc P rather than Px.
W ords and W ord-Com binations to Be M emorized
on account of, associate, avoid, come + миф., completely, confusion, gaseous, either... or..., except, exist, extraction, include, introduce, list, molecular, neither, quantitative, rapidly, rather than, refer to, rubber, since, solid, stable, symbol, volume, yet
Ex. 6. Give the Russian equivalents for the following:
introduce smth., a list of “atomic weights”, on account of, refer to the names of the elements, acquire a quantitative significance, cither... or..., exhibit allotropy, that is to say, exist in different forms, in the same physical state, take an example, from among gaseous elements, yet, be completely different, whereas, exist in pairs, avoid confusion, for example, catch fire in air, there is no way of, both... and..., rather than
Ex. 7. Give the English equivalents for the following:
химический символ, шведский химик, из-за (на основании), с до исторических времен, быстро изменяться, либо... либо.. проявлять (какое-либо свойство), в одинаковом состоянии, привести пример, оба, как... так и..., однако, тогда как, например, воспламеняться на воз духе, при комнатной температуре, сколько, таким образом, а не...
Ex. 8. Fill in the blanks with prepositions where necessary.
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