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62. one. One . . :


, . We found new routes of synthesis, the older ones being unsatisfactory.

, . For our purposes we may think of a molecule of pyridine as being just like one of benzene.

. The fundamental reaction in this synthetic upbuilding is a photochemical n.

. , one, , . :

, . This process is the one to be associated with reaction in alkaline solution.

, , . Overflow from one plate to the one below is by means of the side arm.

, , - . Since normal paraffins were inert, it was likely that the tertiary C-H bond was the one reacting.

, . This method is not the one to use if the isolation of a pure alkali metal alkyl is desired.

63. that, those. . ( of) ( III ). :

, , . The results were very favourable, especially that of Jones and those obtained with new compounds.

, . The reaction is similar to that observed by us.

. The rate is identical with that of the uninhibited reaction.

. The properties of covalent compounds are quite different from those of electrovalent compounds.


, . Many of the separations are carried out by G. L. C., the only exceptions being those of mixtures of low boiling-point constituents.

- . The potentials of carbon and nitrogen increase over that of boron owing to the greater nuclear chargen.

, , . Electrophilic reagents are those which seek electrons, the most common being positive ions.

, , , . Thus the Geneva name for methyl alcohol is methanol, and that for ethyl alcohol is ethanol.

, . The constant for the formation of the derivative from cyclopentanorie is about twice that from acetone.

64. the former, the latter. The former... the latter ( ) , , the former , a the latter . :

. . Polyesters and polyamides are spinned from melts. The latter are more polar.

- , 6-, - . The -electrons can be more easily polarized than 6-electrons, so the former are commonly referred to as mobile electrons.

, , . The rates and molecular weights are affected by lowering he temperature, the former being decreased and the latter increased.

. The latter .

65. . .

7 . . 97


-, -est.

, .. This cube is small but that cube is smaller.

. This is the smallest cube.

than. , CD. Segment AB is longer than segment CD.

one (. 62) that, those (. 63), of, in, for, at .

: more, the most , : difficult, more difficult, the most difficult.

, , : cleverer = more clever; cleverest = the most clever; luckier = more lucky; the luckiest = the most lucky.

( ) , : good, better, the best; bad, worse, the worst; little, less, the least; much, more, the most.

66. + + . as...as, ( )... , ... .

:

, . This reaction is as fast as that described above.

, as...as twice, three times, .

:

. The new procedure is twice as effective as the old one.

, XIV 10 VIII. Owing to


a similar resonance, the half-life of XIV was found to be ten times as long as that of VIII.

[. , . , , , . .

( ). This substance reacts half as fast (as the other one).

( ). This substance reacts one third as fast (as the other one).

( ). This substance reacts one tenth as fast (as the other one).

67. as + () + as possible. as + () + as possible, ( ) + .

:

. Experimental data were presented in some detail and discussed as thoroughly as possible.

, , . provide as much cooling surf as possible, annular tubes are used, the catalyst being in the annulus.

, . We shall, accordingly, lay the greater emphasis upon the second point of view in order to be able to treat as large a number of reaction as possible.

, . Care should be taken that the packing is as uniform as possible.

68. : not so-f- () -fas. ... . :

, , . This catalyst proved not so effective as alumina.

7* 99


69. the -}- ...the -f-. ....

, . The lower the electronegativity of the metal the higher the reactivity of its organometallic compounds.

, , . .The higher the energy of the bombarding electrons, the greater the number of secondary electrons to be emitted.

. ... , the . :

, . This demonstration is the more convincing the greater the variety of adsorbate vapors.

, . The effect of secondary sub-stituents will be greater the nearer they are to the point of attachment of the primary substituent to the rest of the molecule.

, . A compound is considered more stable, the smaller its potential energy.

( ),

70. Careful, carefully. .

careful . carefully . :

, . As to the heat of the reaction it had to be carefully controlled.

, , . This section, con-


cerned with the behaviour of optical isomers on melting, should be studied carefully.

, N- -. The product obtained has been shown by the careful investigation of F. M. Banfield and J. Kenyon to be the N-phenyl ether of the oxime of a ketonic hydroxylamine.

71. Characteristic of. , characteristic of , , , .

:

, . These reactions are those exhibited by the particular functional group characteristic of that homologous series.

. Among cyclic esters the property of undergoing reversible polymerization is characteristic of: and peculiar to the 6-membered rings.

72. Conventional, conventionally. , conventional , , conventionally .

:

, , -. These rules are convenient because they are in terms of conventional chemical symbols that are familiar to all organic chemists.

, . A homogeneous system is one which is conventionally defined as one whose properties are the same throughout its extent.

73. Different. different , , , .

:

. The correlation of one series with another by the use of optical rotations is a very different matter.

, . The properties of covalent


compounds are quite different from those of electrovalent compounds.

. A different procedure was discovered by Gabriel.

, . We meant that we could obtain different results.

, , , , , , . Unresolved components from a primary fractionatiou often can be resolved elegantly by chromatographing on a second column operated at a different temperature, or with a different buffer solution, or in a different cycle, or with a different resin.

74. Extra. , , extra , . :

- , . This structure is not compatible with the spectral data, in virtue of the marked steric effect expected from the extra methyl substituent in the side chain.

- , , . Extra negative substituents will further assist S-rep-lacement and hence rearrangement.

, , , , - . The extra stability due to conjugation is greater the more the -electrons are shared in the structure.

75. Fair, fairly. fair , , , , .

:

, . At most these bond energies are only a fair approximation to the actual energy required to rupture a given bond.

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

fair , , fairly , , : fairly good .


fairly , , , . :

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

, . These substances have been chosen in such a way as to cover a fairly large number of different types of compounds.

76. Marked, markedly. to mark , III marked , . markedly . :

. Induction too has a marked effect on the electron density of the ring.

, . The equilibrium initial stress is seen to he markedly affected.

. At the point the current decreases markedly.

, . Beeck has suggested that a very small amount of impurity can have a very marked effect on surface.

, , . It must also be borne in mind that the gas is a fluid which changes its volume markedly with change of temperature.

77. Occasional, occasionally. occasion occasional occasionally . , , , occasional , , , , a occasionally , , , , .

:

. A precision potentiometer is available for occasional use.

, , . Since the chains are exceedingly long they are linked together only at occasional points to produce a non-plastic structure.


, , . Unit cell may contain one, two, or, occasionally, more than two layers.

78. Particular. , , .

:

, , . It is obviously desirable to have a scale of temperature independent of a particular property of a particular substance.

V () . Whatever the particular form of V (r), there are solutions, which are spherically symmetrical.

. The data provided vary with the purpose and scope of each particular investigation.

79. Previous, previously. .

:

, - . Extraction of cornstalks, previously hydrolyzed with dilute hydrochloric acid according to Morgal.

, , . . , . , , , , , . : These compounds have been previously assigned the following structure .

:

. Previous systematic investigation of unsymmetrical ketones in the Schmidt reaction have been concerned principally with the effect of branching in alkylgroups.

. Nearly all previous studies on the ion exchange


behaviour of zirconium and hafnium have been limited to investigations of the separation of these two elements.

, , preliminarily, , tentatively.

80. Repeated, repeatedly. to repeat repeated . repeated , on repeated occasions repeatedly.

:

, , . Upon repeated equilibration with sodium chloride small amounts of titratable hydrogen were found even after the seventh equilibration.

. The repeated use of BET plots for measuring surface areas revealed several advantages over the point method.

. Production samples of mo-noethylene glycol were purified by repeated fractional distillation.

. Columns may be used repeatedly.

81. Suitable. ( ), , ( ).

:

. Under the action of suitable reagents.

. After a suitable time the amount of nitration products is determined.

, , . Suitable catalysts, have been found to greatly reduce the temperature required to effect cracking.

, , ,


. The advantage of this particular reagent is that the thioureas derived from it have melting-points within a suitable range.

82. Tentative, tentatively. tentative , , , .

:

, . Our experiments have led to the tentative conclusion that these mixed solvent systems facilitate cellulose reactions.

, , , .

No particular vibrational mode can be suggested at present which might account for this correlation which must therefore be regarded as a tentative one.

tentatively, , , , , , . :

, NH . In addition, the weak band was noted by some workers and assigned tentatively to an additional NH absorption.

. Further evidence bearing on the correctness of a tentatively assigned electrode reaction can be secured.

83. : hitherto, generally, previously, recently, already, long, now, then, since, never.

, Present Past Indefinite, - to be, ( ) .

:

This reduction is generally made by choosing the critical state as the reference state. Such a reaction would generally be held to proceed through a substituted carbonium ion. They generally considered this reaction as proceeding via two routes. We have hitherto studied the metal complexes of the bidentate ligands, 2,2'-bipyri-dyl and 1,10-phenanthroline. The simple modification of Trouton's rule has not previously been employed as a basis for the comparison


of liquids. We have previously given reasons for disfavouring this model. The other solution is that of Melander and Myhre, who have recently pointed out, that the unsymmetrical structure of composition SH+ need not correspond to a potential minimum along the reaction co-ordinate. The rates have already been measured at +20 by a rapid-reaction technique. Evidence that these reactions are proton-transfers has already been given. The first stable crystalline ethoxyformic anhydrides have only recently been reported, although two methoxyformic anhydrides with similar properties have long been known. We have now developed an apparatus to follow reactions photometrically at temperatures down to 140. We have then examined the lability of the bis-series of complexes. It has since been shown that this result is not confined to the aqueous acids first studied. There has since been little systematic work on the complexes formed by this interesting ligand.

.

:

Since Werner's time it has been generally assumed that sulphur-metal bonds are involved in such compounds. Spectroscopic studies of living polystyrene have been recently reported by Ku-wata. The infrared spectrum of N'-, N", N'"-triethylborazole has not been previously described. Filter-sheet separations on 3MM paper were effected on paper which had been previously extracted. We have now prepared a series of dimercapto-alkanols, the only other representative of this class to have been prepared hitherto being l,3-dimercaptopropan-2-ol, 3,4-dimercaptobutan-l-ol, and 4,5-dimercaptopental-l-ol. The two glycosides have been isolated previously from the bark of Engelhardtia formosana engelitin and isoengelitin. In particular, the magnetic properties of ammonium vanadium alum have been studied previously.





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