b) 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
c)
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 as
noble gases. 2. Some chcmical phenomena arc not easily
accounted for.
3. Symbols began as a simple shorthand for the
names of the
elements.
4. 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.
85
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>, N
2
, 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 o rd s an d W o rd-C om binations to Be M em orized
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. G ive th e R u ssian equivalents fo r th e 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, bo th ... and..., rather than
E x. 7. G ive th e E nglish equivalents fo r th e 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 th e b la n k s w ith prepositions w h ere
necessary.
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