Санкт-петербургского государственного университета высшее профессиональное образование т. А. Степанова, И. Ю. Ступина
Lesson 21 ' ГРА М М А ТИ КА : Причастный оборот в функции дополнения. Section I
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| Lesson 21
' ГРА М М А ТИ КА : Причастный оборот в функции дополнения. Section I Ex. 1. P ra c tise y o u r p ro n u n cia tio n . a) require [rTkwaio], completion [kom'pli:Jbn], extremely [iks'tri:mh], neutralization [,nju:trolai'zeijon], presumably [pri'zjuimobli], hydroxide [hai'droksatd], collision [кэ'Ьзэп], precipitate (n) [pn'sipitat], precipitate [pn'sipiteit] (v), appreciable [o'pri:Jobl], circumstancc ['s3:komstons], irradiation [i.reidt'ei/an], ultraviolet [.Altra'vaiaht], neutron ['nju:tron] b) thew'rateuof ajre\action, foruits„com\pletion, the„'numberuofu collisions, therejs^'littlc de\lay, itJsu'not un\usual, withu'visible\light c) On the 'other/Tiand, | io n ic oxi'dation-rc'duction re'actions | are 'sometimes 'very \s lo w . Ex. 2. P ay atten tio n to th e s tru c tu re o f th e follow ing w o rd s, tra n s la te them in to R u ssian : a) ultraviolet, ultramodern, ultrashort, ultrasound, ultrasonic b) twofold,.threefold, fourfold, tenfold, manifold c) ferric — ferrous, nitric — nitrous, sulphuric — sulphurous, stannic — stannous ф E x. 3 . D efine th e m eanings o f th e w o rd other in th e follow ing sentences: 1. Chemists and other scientists use the word “theory” in two different senses. 2. The first meaning is “a hypothesis that has been verified”; the other meaning is “a systematic body of knowledge”. 3. On the basis o f the experimental results of Priestley, Schcelc, and others, as well as some very fine experimental work of his own, Lavoisier established a new conccpt of combustion. 4. There arc more compounds of hydrogen known than of any other element. 5. Other conditions being equal, the conclusion was made that it proceeds faster. 6. The silver-grey coating on its surface is characteristic of selenium, anothervariety ofthe clement is rod. 7. There arc some reactions which procccd vciy quickly, on the other hand, there are other reactions which are extremely slow under the same conditions. 8. It is not easy for them to work together because they don’t like cach other. 9. The results that were obtained in this experiment arc not reliable, that implies that wc should tiy some other approach than we have just employed. Ex. 4. F in d th e p red ica te, th e su b je c t a n d th e ob ject in th e following sentences: 1. Wc could observe the solution changing colour with time. 2. Some catalysts acccleratc reactions, others make them procccd slower. 3. It was interesting to watch Dr. N demonstrating his experiments. 143 Text 21 A Every chcmical reaction requires some time for its complctiQn, but some reactions arc very fast and some arc very slow. Reactions between ions in solution without change in oxidation state arc usually extremely fast. An example is the neutralization of an acid by a base, which proceeds as fast as the solutions can be mixed. Presumably nearly every time a hydronium ion collides with a hydroxide ion reaction occurs, and the number of collisions is vciy great, so that there is little delay in the reaction. The formulation of a precipitate, such as that o f silver chloridc when a solution containing silver ion is mixed with a solution containing chloridc ion, may require a few scconds, to permit the ions to diffuse together to form the crystalline grains of the precipitate: Ag*(aq) + Cl'(aq) -» AgCl(c). On the other hand, ionic oxidation-rcduction reactions arc sometimes very slow. An example is the oxidation of a stannous ion by a fcrric ion: 2FC5* + Sn*’ —» 2Fc2* + Sn4\ This reaction docs not occur every time a stannous ion collides with one or two fcrric ions. In order for a reaction to take place, the collision must be of such a nature that electrons can be transferred from one ion to another, and collisions that permit this electron transfer to occur may be rare. An example of a reaction that is extremely slow at room temperature is that between hydrogen and oxygen: жүктеу/скачать 5,96 Mb. Достарыңызбен бөлісу:
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