.


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, , . minimize

14 . . 209


decomposition of the iodine-containing compound, he employed alkaline hydrolysis.

, bring the intensity of one of the peaks to a standard value.

, -, -. Colour test detects only those organometallic compounds, which are sufficiently reactive to undergo a rapid halogen-metal exchange reaction with p-bromdimethylaniline.

. . :

. Rotation spectra can be used to measure bond lengths.

. had taken extraordinary steps to ensure the precision and accuracy of measurements.

202. . enough too .

:

, . In symmetrical structures the = absorption is often too weak to be detectable.

, , 0 . It is possible to prepare the intermediate mixed anhydride which is stable enough to be isolated at 0 or below. -

N-- , . A number of N-vinyl derivatives of imides are stable enough to be prepared and polymerized.

, , . The reactions were too rapid to be followed by other methods of phag assay.

, . Usually hydrates or hemiacetals of simple aldehydes are too unstable to be isolated.

, . Any absorption in this region is too weak to be observed.


, . Some molecules are large enough to be seen in the electron microscope.

, . Usually hydrates are too unstable to be isolated.

, - . Precipitation reactions are too general to be of value.

, . Equilibrium concentration is too small to measure.

, . The quantity of blood group substance is too minute to affect the test.

, . Ethers are basic enough to combine with strong mineral acids to form oxonium salts.

203. . , : to form, to produce , to give, to yield ( , ), to become , to lose . .

:

PtCl2 , - , , Pt CoCl2. The active PtCl2 may condense to give the non-reactive polymer or it may be reduced by CO to give Pt and CoCl2.

, . Vinylacetylene under pressure with or without the usual catalysts is readily polymerized by heat to form viscous drying oils.

, - . Vinylacetylene reacts with Grignard reagents to form the organo magnesium halide.

, . Ethylene reacted with mesityl oxide to produce two monaodducts and a diadduct.

, . The crystal units had rearranged to produce a pseudomorphic form.

II , . Compound II can be hydrolyzed to yield the free amine.

14* 211


204. . (. 196) , , , . .

:

. Instead of combining with a nucleophilic reagent, the carbonium ion in this case donates a proton to a base to become an olefiu.

. This compound is oxidized by silver oxide to lose one hydrogen atom.

- . Alkoxy groups in orthoesters are readily replaced by alkyl groups to produce acetals.

, - 20 , . Chavanne observed that trans-di-chioroethylene is consumed by base to give chloroacetylene twenty times as fast as the cis isomer.

205. . .

:

; , , . The result to be expected is important for our investigation; The result that is to be expected is important for our investigation.

the first, the last, the only.

:

, , . Isobutane is the only isoparaffin to attain any industrial importance in alkylatiou, yet when compared with other isoparaffins, it is unique in some respects.

, . Klason was the first lignin chemist to develop a theory of the formation of lignin and to propose a possible structural formula of an aromatic nature for it.


-, , . Thomas appears to have been the first to focus attention on this type of reaction.

, -, , , . They appear to be the first to have suggested the currently accepted reaction mechanism in terms of modern physical organic chemical concepts.

. (. 163).

, . The mercury porosimeter method to be described in the next section.

(: ; ) . The reagent chosen in a particular case depends upon the compound to be sulfonated and the number of sulfo groups to be introduced.

, , . For other reasons soon to be discussed manganese forms a dicyclopentadienide.

, , . 100, . The method of detection developed by Lovelock to be described on page 100, is also based on ionisation by irradiation.

206. . : must (may, can) + have + /// ,

: must , may, can , , , , .

:

, () . must have finished his experiment.

, , . ,


, it is possible, it is likely.

:

, . It is possible that some of the products isolated may have resulted from the alkylation of others.

1,3--, , , 1,5-. The only product isolated was 1,3-diphenylpyrazole, although the 1,5-isomer may also have been present.

, , , 3,1% , , 88. On the assumption that a dimer is the only association product, a calculation shows that 3,1% of the boron trifluoride molecules may have associated at 88ѻ.

, , , III, . Following the suggestion of Rosenheim and King that the substance may have arisen by the transformation I>II, Cook and co-workers synthesized the hydrocarbon indicated.

, 4, 5, 6 . This route may have been followed in reactions 4, 5, 6.

, , . The third hydroxyl group originally present must have combined with the aldehyde group to form a lactol ring.

, VII , . . VII, , VI. When an equimolecular mixture of the two was heated, product VII was found to be free from radioactivity after rigorous purification, i. e. the allylic group in VII must have been derived solely from VI.

, 25 , ; , , , . The products obtained at 25 were more highly chlorinated, indicating that the nethyl hypochlorite must have decomposed and reacted as free chlorine.

, , , . They point out that the ester must have undergone acyloxygen fission.

, , . The three phenyltungstic acids must have been polymeric.


207. -. , -. , ( ) . : , . , , , .

- , : , . , . , .

(. 209, 210, 211, 215), -, .

-. : , . , .

, - , , . , - to consider , , to believe , , to choose , 嗫, to work out, , to give , , to credit , . .

:

, , . The uptake of oxygen is believed to be the rate-determining step of the reaction.

, . These data must be considered as being largely approximate.

- . . .

, . . : , : to say , to see , to hear ,


to state , to report , to announce , to believe , , to suppose , to think , to expect , , to know , to understand , to consider , to assume , to declare 1.

, , , , , , . , . . : : to seem , to happen , to appear , (to say , to inform . .), (to think , to consider . .), (to hear , to hope . .) 2.

- 3 . , , ( to be ), -, - as + , () .

, 1961 ., 100 -. 1962 . 140 4, 158. , - .

:

The Conference is scheduled to take place in August.

The author was destined to be disappointed.

Lack of oxygen is credited to make people lose health.

Reaction 2a may be written as proceeding by the following mechanism.

1 H. . . . ., 1959, . 9394.

2 . . . . , 1961, . 93.

3 . . . . . ., 1961, . 4445; . - . . ., 1961, . 278279.

4 . . . . , , . ., 1962, . 284-285.


The reaction was feared to take a different course.

This method, previously mentioned as affording good result, is widely used.

Each corner is understood to be the location of a carbon atom.

They acknowledged the reaction to be exothermic.

Carcinogens may be defined as being chemical and physical agents.

The angle V between the acute disectrix and either optic axis was measured to be 1,3 for bulk crystal specimen B. The possibility of demonstrating specific parts of the intestinal tract as being responsible for the intoxication seen in Eck-fistual animals was explored in two ways. Although the 4 11 state of NO has been predicted by Mulliken to be a bound state, it is considered separately because insufficient spectroscopic data are available. It is this force which may be thought of as holding the molecule together.

The ground station will be at Rumford, Maine, and will be comparable with that used for Project Echo. In this case the radio frequencies are proposed to be in the neighborhood of 4,000 m.

The missile to be analysed is idealized as a long beamlike structure that has a finite number of lumped masses, mass moments of inertia, flexural stiffnesses over a short interval of length. The masses are assumed constant at some particular time which means that the mass change during the time for a single vibration is small and negligible.

G. E. Coates (Organo-metallic compounds 1956) writes of this substance as an obscure compound of unknown origin.

While we have been talking of the surface of a solid catalyst as the site of the catalytic reactions, it is by no means clear that such is always the case.

Inelastic collisions between atoms may be categorized as involving ionization of electrons, rearrangement of electrons, or electronic transitions.

208. -. - , .

accept, to acknowledge, to admit, to advertise, to allege, to allude, to analyse, to announce, to anticipate, to appear, to appreciate, to be apt to, to argue, to assert, to assign, to assume, to bear out, to believe, to calculate, to categorise, to be certain, to chance, to characterise, to choose, to cite, to claim, to class, to classify, to comment, to compute, to conceive, to conclude, to confirm, to consider, to construe, to corroborate, to count on, to credit, to declare, to deduce, to deem, to define, to demonstrate, to deny, to depict, to describe, to designate, to desire, to destine, to determine, to devine, to diagnose, to disclose, to dislike, to envisage, to establish,


to estimate, to evaluate, to expect, to explain, to fancy, to fear, to feel, to find, to fix, to formulate, to give, to guarantee, to guess, to happen, to hear, to hold, to idealise, to identify, to infer, to imagine, to be inclined, to indicate, to intend, to interpret, to judge, to know, to label, to learn, to like, to be likely, to list, to look to, to look upon, to mean, to measure, to mention, to note, to notice, to observe, to obtain, to order, to perceive, to permit, to picture, to place, to pledge, to point to, to postulate, to prefer, to predict, to presume, to pretend, to propose, to prove, to put forward, to be proved, to quote, to rate, to rationalise, to read, to realise, to recalculate, to reckon, to recognise, to refer to, to regard, to remember, to report, to represent, to repute, to require, to reveal, to rumour, to say, to schedule, to see, to seem, to show, to speak of, to state, to substantiate, to suggest, to summarise, to suppose, to support, to suspect, to be sure, to symbolise, to take, to talk of, to think (of), to treat, to trust, to turn out, to understand, to be unlikely, to view, to visualise, to want, to wish, to work out, to write (of).

. , , , , . , -, , , , to assume, to consider, to choose, to hold, to reckon, to take. .

:

, 2,5. De Boer reported the density of the substance to be 2,5.

, 2,554 2,559. They determined the density of the substance to be between 2,554 and 2,559.

, S". The crystal can be pictured as located at the center of the circle S".

, . Each crystal may be envisaged as a reciprocal lattice.

:

Higher open chain olefins were thought to arise either by direct polymerization or by ring opening from the polymethylenes. Production of saturated hydrocarbons was considered to bo due either to hydrogenation of cyclanes, causing ring opening, or to splitting of side chains attached to a polymethylene nucleus.


Ethane was regarded as primary decomposition product; at low temperatures the amount formed, although small, was nearly proportional to the amount of ethylene decomposed. Methane was considered a secondary product since its proportion increased as the heating time was prolonged.

- to think to consider, to regard to consider.

209. 1. , , .

: + - + + . :

, 14,8%. They calculated the methoxyl content of spruce protolignin to be 14.8%.

, 4,6%. Sandelin determined the methoxyl content of sprucewood to be 4.6%.

, . Ewald found this to be true for hexaphenylethane.

, , , . We can also write the heat energy absorbed in such a process to be as follows.

, 258,1 /. Wartenberg recalculated the heat of formation of boron trifluoride to amount to 258.1 kcal per mole.

0 , . . , , , , 80%. At 0 and low pressures, conditions under which Roberts had claimed the hydrogen layer to be complete, the layer is in fact only 80% complete.

1. to see, to hear . . to.

, . I see her run (= to run).

2. , ( ) . :

, . The scientists believe to have discovered a new compound.

1 Complex Object.


, , . We still have a long way to go before we can claim to have solved the problem of sexuality in bacteria.

, . Loder claimed to obtain pure boron trifluoride. , . Farr believes to have proved his point.

210. (). : + - + + + (). :

-, , , . It seems possible to picture solvent molecules participating in the activated complex in these polar solvents just as they did in the inert solvents.

211. 1.

, - - it:

it is known ; it is demonstrated ; it is thought ; it is considered ; it is found ; it is suggested ; it is said ; it is taken , ; it is believed , it is regarded ; it is supposed ; it is reported . .). : , . It is said that he is very capable. , . <<It is known that he has come. , . It is believed that they work well.

, , .

: + - + + .

:

, . The mistakes are thought to be negligent.

, . Tetrahydrofur-furyl alcohol is said to be a suitable medium for reactions of this sort.





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