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233. affect. -, -. :

X Y. X was affected by û.

. The results were affected by the presence of impurities.

. The rates and molecular weights are affected by lowering the temperature.

He , . It is not clear to what extent this polymerisation is affected by orientating influences in the aromatic ring.

. to be affected , , to be unaffected not to be affected , .


:

, . However, the equilibrium initial stress is seen to be markedly affected in accord with similar observations of Wood and Roth.

, . In ether and similar solvents the frequency was unaffected, but a slight fall was observed in aniline and in isopropyl ether.

-, , . The ratio of the two isomeric chlorobutadienes present in the reaction product remains practically unaffected.

. The mere mechanical presence of an impurity does not affect the Curie point.

234. To assume. . -, :

-. This molecule assumed the cis-configuration.

-, - (. 207) :

, , . The products of such reactions have frequently been assumed to be dimeric for no other reason than they were obviously not monomeric.

, , . Steric influences in the formation of the head-to-tail arrangement may therefore be assumed to cause the heat of polymerization to decrease.

235. To a t t e m p t. :

. We attempted to carry out this investigation.

to attempt , .

. We attempted this investigation.

. III :


. The attempted investigation proved to be a success.

236. To be available. - , not to be available, to be unavailable , . available , a unavailable , . :

, . The usual means of identifying organic compounds by melting points is either not available or far less characteristic in many cases.

. Far more definite data are available on the reactions of these two reagents with the sugars.

. to be available , a not to be available . :

- , -. If the ortho position is available the migrating group does not take the para position.

. There are six equivalent positions available in benzene.

- . Ortho positions are unavailable.

237. To be bound. to bind , , ( ):

( ). This compound is bound to react.

. Hydrogen is bound to be dissolved and chemisorbed by the adsorbent.

238. To claim. . -, , :

. This new procedure has claimed the attention of many chemists.

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


, , , . Ansbacher further claimed that the acid was essential for the growth of chicks.

, , , . Although it was claimed some years ago that these substances may be obtained by the reaction of Grignard reagents it was shown later that the claim was in error.

239. To develop. , , . , , , . , . :

, . It is the radio active method originally developed by Hahn and his co-workers.

, , . Instead the emphasis will be placed on the tubular types, where the geometry is simple enough to develop quantitative design procedures.

, . A novel empirical method was developed recently by Franklin wherein the resonance energy is calculated from group equivalents.

, . The equations for the over-all rate as developed by Hurt are given in this chapter.

240. To estimate. , , , .

:

, 20 30% . Equation may be used directly to estimate the required difference, which often amounts to twenty or thirty per cent for each degree of ionization.

5. Pauling has estimated the radii of these volumes and they are reproduced in Table 5.

. This fact can be used to estimate the number of amino groups in a compound.


, . Although the body of data is growing, it is still not possible to estimate the equilibrium conversion for all reactions.

to estimate - (. 207).

, 10-11 . The time for this inversion has been estimated to be 10-11 seconds.

241. To follow. : 1) (-), 2) , , , 3) , .

:

. Multilayers of different substances may be deposited above one another, and their interdiffusion might be followed with the help of X-rays.

, . One of the procedures described in Part I has been followed here.

. Then followed the discovery of a new compound.

1. The reaction is followed by temperature rise : .

2. :

X Y. X is followed by Y.

To, , . That opening of the epoxide ring is not followed by displacement of the bromine by the alkoxide oxygen is not surprising.

242. To hold. , : 1) , ( ); 2) , ( -, . 207); 3) , ; 4) (, ); 5) , , , .

:


-, . These correlations appear to hold for many hydrocarbons.

, , , . They held that this observation showed the reaction to be intermolecuar.

, , . The open-pore theory holds that adsorption takes place normally in layers on the walls of the capillaris.

, , . According to Halsey, this theory should hold whether localized or mobile adsorption is assumed.

, , . This holds of course for the light elements.

243. To involve, involving. , to involve . , , . to involve (. . 2627) , , , , , , , , .

:

, -, . The selection of matched pairs of thermistors and their reproducibility still seem to involve considerable difficulties.

, , . The magnitudes for all of these quantities, except the last, involve the question of standard states.

. The design of reliable apparatus for this purpose involves a fair number of difficulties.

. The Fisher method involves certain losses.

m- , - . With m-fluorotoluene the reaction is proved to involve the position para to the fluorine atom.


, --, , . The reasons for the OH absorption have already been discussed and it seems to be generally accepted that crystal forms are one of the factors involved.

. Every field of chemistry involves different chemical reactions.

to involve .

:

. Chemisorption on oxides and similar substances involves appreciable activation energies.

. Diffusion of the adsorbate may involve appreciable time.

to be involved . involved too, very, extreme.

:

, . The problem is far too involved forone to be able to solve it.

- , . Proof of the formula for d-galactose is too involved to be given here.

, , , , . The problem is undoubtedly very involved and conclusions drawn solely from viscosity measurements must be treated with reserve.

involving , , , .

:

-. A reaction involving the homolytic scission of a carbon to bromine bond.

. Reversible reactions involving the simultaneous formation of a volatile and non-volatile product are often forced to completion.

, . Condensation polymers are such in which the monomers interact by chemical processes involving the elimination of water or other simple molecules.

. Numerous


experiments involving the preparation and redistillation of diacetylene have been carried out without mishap.

. It would be highly desirable to have quantitative data involving kinetically controlled reactions.

involving , :

, , . However the terminal reaction involving the mutual reaction of ions of like charge, should be relatively unimportant.

244. To n e e d. , .

:

, . In any case a large excess of ammonia is needed to avoid the formation of the secondary derivative.

, , , , . The number of plates needed for chromatography is much higher than that required for distillation.

, , , , , . On this view the constitution of the cation of these coloured salts is that of a free radical, there being one less electron than is needed for a compound of normal valency.

. to need to , , . :

5%. The impurities need not exceed 5 per cent>.

. Only recent data need be taken into account,

, . The solute molecules need not travel far in the liquid phase, where the speed of diffusion is small.

. These processes need not be considered.

245. To offer.


: , , , . , :

. All conductors offer fairly low resistance to the flow of electric current.

. Hinshelwood offered a new explanation to this phenomenon.

246. To r e f e r t o.

1. , , , :

, . Here the heat of formation refers to that from atoms in arbitrary energy states.

2. , to refer to , , , :

. In considering this point we must refer to the recent work by Smith.

3. : to refer to... as, to be referred to as , , :

, . In the very concentrated solution of polymers the low molecular weight component is usually referred to as a plastici-ser, rather than a solvent.

- . The -electrons are often referred to as unsaturation electrons.

247. To suggest. , , , (-, . 207). , , ( , , . .), (, . .).

:

, , , , - . They held that this observation showed the reaction


to be intermolecular and suggested that a reactive acyl hypohalite was formed as an intermediate.

. They suggested a new procedure to obtain these valuable compounds.

1. , to suggest :

, , , . This suggests that the corresponding compounds obtained from the isomeric bromepoxides are not identical.

2. to suggest , :

. Two possible mechanisms suggest themselves for these reactions.

248. To take. , :

1) :

. The molecules took the following configuration;

2) , , (-, . 207);

, , . We take the heat of formation to refer to formation from atoms in arbitrary energy states;

3) , ( ). ,

. It took them over 5 hours to carry the reaction to completion;

4) , , (, . .):

() . They took the X-ray patterns of these compounds.

249. To treat. , : , , .

1/ . . 257


:

1906 . , . In 1906 Einstein treated theoretically the case of a dilute solution containing spherical particles.

. The theoretical aspects of the phenomenon will not be treated until later.

, . It is very convenient to treat the subject of chemisorption from a thermodynamical point of view rather than from a statistical one.

.

250. undergo. To undergo , .

:

. Highly reactive ions undergo isomerisation.

. The radical eventually undergoes a disproportion reaction to quinone and hydroquinone

, . Among cyclic esters the property of undergoing reversible polymerisation is characteristic of the 6-membered rings.

. undergo + .

:

. The element in this state must undergo instant oxidation by loss of electrons to neighboring solvent or reactant molecules.

, , , , , . The fact that the molecular weight was not affected by increasing the temperature indicated that the lignin molecule is not a loose aggregate of smaller molecules which undergo thermal dissociation.


', . It was claimed that the cellulose did not undergo any appreciable change on treatment with phenols.

- - , , . Tertiary alkyl- or cycloalkylarenes undergo dealkylation most readily, secondary alkylarenes undergo only a partial dealkylation, and primary alkylarenes are stable.

251. To be useful. to be useful . to be useful , .

:

- , . The Friedel-Crafts type of reaction has been useful during the past three-quarters of a century.

, -, . Sodium hydroxide does not appear to be as generally useful as triethylamine.

. Solubility parameters are useful for selecting solvents.

. The most generally useful expression For giving the composition of a solution is the mole fraction.

17*

 






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