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Proceedings of the Chemical Society, Vol. 6, No. 90 |
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Proceedings of the Chemical Society, London,
Volume 6,
Issue 90,
1890,
Page 169-178
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摘要:
P It 0C E E D I N G S OF THE CHEMICAL SOCIETY. No. 90. Session 1890-91. December 18th, 1890. Dr. W. J. Russell, F.R.S., President, in the Chair. Messrs. William J. Butcher, Thomas Platt's, Charles T. Branson and Wm. H. Barraclough were formally admitted Fellows of the Society. Certificates were read for t,he first time in favour of Messrs. Charles Norris Adams, M.A., 128, Chorlton Road, Manchester ; Robert John Brown, 76, Grenville Street, Stockport ; Frederick John Bloomer, 7, Boundaries Road, Balham, S.W.; Robert Bond Greaves, 154, Cemetery R'oad, Sheffield ; Frederick William Harrold, 12, Hereford Gardens, Park Lane, W. ; Edgar J. Millard, 50, Hillside Road, Stamford Hill, N.; Frederick Herbert Moore, 45,St. Mary's Road, Peckham, S.E. ; Michael Samuel Bickering, 40, Price Street, Burslem, Stoke-on-Trent ; William Jackson Pope, South Street, Ponders End; A.H. Tapp, The Gables, Shortlands, Kent. The following papers were read :-98. " Note on the constitution of dehydracetic acid." By Norman Collie, Ph.l)., F.R.S.E. During t,he investigation of the effect of heat on ethylic 6-amido- crotonate, the production of lutidone derivatives seemed to point to a close resemblance existing between the products formed from the crotonic salt and ethylic acetoa,cetate when heated. The author was, therefore, lead to enquire into the formulae which various in-vestigators had given to dehydracetic acid, the condensabion product formed when ethylic acetoacetate is distilled. This peculiar acid has for long been the subject of investigation, and the various formulae which have been suggested are all open to criticism, as Feist in his very excellent paper on this acid (AnnuZen, 257, 253) has shown.170 The formula given by Feist, howevei-, is itself inadequate. The pro- duction of the acid takes place according to Feist as follows :-CE;fi*OIH-__ czH,qyo CH,-f/-O-$lO HC-CO*JOC2H5-Hl-C:C(OH).CII,= HC-CO.C:C(OH)GH,+ ‘LC,H,OH. He discards the carboxylic group in his formula, as Ostwald has shown that the conductivity of the substance precludes the assump- tioii that it is a true acid. The formation of a dichloride by the action of pcntachloride of phosphorus, which apparently involves the displacement of two hydroxyl groups by chlorine ; the pyoduction of orcinol by hydrolysis with baryta water; and the acid properties of the monomethylic derivative noticed first by Perkin cannot, however, be interpreted easily by Feist’s formula.The formula which the author proposed appears not only to account, for all the methods of formation and interactions of dehydracetic acid in cases in which Feist’s formula is satisfactory, but also in those in which Feist’s formula is evidently insufficient. It is as follows :-CH; C 0.CH; C :I0H,I CH.C 0-C Hz*C 0 IH czli5q = CH3*C0%H2*$::CH.C 0.C H; C0o-.------.-I + CZHSOH + C,H, + HLO. The tautomeric form would be, therefore, CH;C (OH):CH*~:CH-C(OH):CH*CO. 0--__ I The formation of a dichloride can easily be represented, also the existence of an acid rnonomethyl derivative ; the formation of orcinol would take place as follows :-CH3.C(O13):CH.~:CH-C(0H):CH.C:Oo--_r when treated with baryta water would yield CH,*$XCH*C(OH):CH*C(OH):~H YOTI I GOOH [ Geuther, the discoverer of dehydracetic acid, first suggested, in 1566, that it was formed by the dehydration of acetic acid, 4CH,COOH = C,H80a+ 4H20. This idea is shown to be correct if we consider the synthesis of this acid by heating chlopide of acetyl and pyimidiiie, and if we taka acetoacetic acid as diacetic acid, the dehydracetic acid becomes the 2-lactone of tetracetic acid.99. “The theory of dissociation into ions, and its consequences.” By S. C. Pickering. According to the present physical theory of solution, the only change which occurs when hydrogen chloride gas is dissolved in water is the dissociation of the HC1 molecules into their ions : this change Arrhenins said must absorb heat, and, if so, there must have been creation of heat, as heat is, as a matter of fact, evolved during the dissolution. It appears that this difficulty is now met by supposiiig that the heat absorbed in the dissociation of the molecule into atoms is more than counterbalanced by the heat evolved in the combination of electrical charges with the atoms.This involves the idea of these charg3s being things independent of the atoms, and being called into exiht- ence from nowhere, and by no assignable means ; it involves the idea of matter being capable of combining with energy, or an affection of matter, and thereby evolving heat ; and it necessitates the conclu- sion that electrical charges of an opposite sign repel each other, and act an tagonistically to chemical attraction.Such conceptions seem scarcely possible, and are in direct opposit’ion to Paraday’s electro- chemical theory. Calling the ions “allotropic atoms ’’ instead of “ charged atoms ” would seem to be merely a change of name, which obviates none of tJhose objections. The theory would, unlike the hydrate theory, appear to be incapable of giving any satisfactory explanation of the absorption of heat which occurs when many solid salts are dissolved in water. It may also be shown that the potential energy of a dissolved salt must be inter- mediate in marly cases between that of the solid and gaseous salt, a.fact which it is difficult to reconcile with tl~e idea of the dissolved substance being in any sense in an atomic condition. In some cases, moreover, the thermal results attending the dilution of a di1ut.e solu- tion mast lead to the conclusion that the formation of ions from the gaseous molecules absorbs heat, whereas in the same case the heat of dissolution of the ordinary gaseoas salt is found to be a large positivc qnixntity, and must, led to a di imetricnlly opposite conclusion. It must be noticed that the first hypothesis of Clausius-that a few molecules in solution are dissociated into their ions by accidental superheating-would seem to have little in conimon with the present dissociation theory.The second hypothesis of Clausius-that a free interchange of atoms can take pIace between molecules without neces- sarily resulting in the liberation of atoms-would, however, seem to be sufficient to explain all the facts of electrolysis, and it obviates the objections which may be raised against the ideaof there being even a few free atoms in solution. DISCUSSION. Professor RARISAYagreed with Mr.Pickering that many difficulties still remained to be solved before accepting the theories of Arrhenius and Van’t Hoff in their entirety. He thought, however, that :L theory, whatever its nature, could not be regarded as an absolute explanation of phenomena, but merely as a mental picture, whereby phenomena familiar to our senses could be conceived as analogous to those which do not directIy appeal to our senses.It might well be possible that the analogy was a defective oiie ; “we explain,” many phenomena by the “ atomic theory,” but have a very limited concep- tion of an “atom;” and the analogy between dilute solutions and gases must also be accepted merely as provisional-as it means of con- necting together a great number of phenomena which would othw- wise remain isolated facts. By dl means let us draw attention to seeming discrepancies ;to explain them may involve modification of the theory ; but, until we have a better one, let us accept one which correlates a large number of phenomena which have not otherwise been united under any scheme.Mr. PICKERINGsaid that he certainly could not agree with Professor Ramst~y’s contention that the dissociation theory should be received because it explained certain numerical relations, in spite of the fact, which Professor Ramsay appeared to admit, that it could not be sup-ported on any rational grounds. He scarcely thought that Professor Kamsay could be right in saying that the dissociationists would attempt to explain some of the difficulties by stating that energy is a form of matter. If such were the case, all our present science must be wrong; and even though this view might account for Lieat (? matter or motion) being developed when thiR energy-matter com- bined with ordinary matter, we should still not be justified in calling it into existence from nowhere just when it suited our convenience.Professor Ramsay’s suggestion that no molecules could react chemi- cally would lead to the conclusion that no chemical change could occur nnless the molecules were pet-iously dissociated by heat or 173 some other external agency, a conclusion which would obviously be at variance with known facts. Ostwald’s experiment, in which a current produced by static elec- tricity effects electrolysis, can certainly be explained on the dissocia- tion theory, but so also it can, of course, on any other theory; it is difficult, therefore, to see how it can be brought forward by Ostwald as a conclusive proof of the dissociatioll theory. 100. “ The fermentatiori of calcium glycerate by Bacillus ethaceticus.” By Percy I?. Frankland, Ph D., and William Frew.The authors describe the fermentative decomposition of calcium glycerate brought about by a micro-organism, previously isolated and described by one of them (Proc. Boy. SOC.,46,345), and to which the name of Bacillus ethaceticus was given, in consequence of the products, ethyl alcohol and acetic acid, to which it gives rise in several fermenta- tions already stmdied. The products obtained in this fermentation agaiii were principally ethyl alcohol and scetic acid, together with smaller proportions of formic and succinic acids. In the case of each com- pleted fermentation, there was also found a quantity of a fixed acid amounting to about one-half of the glyoeric acid employed ; this acid was insoluble in ether, and in other respects resembled glyceric acid.Lead salts were prepared from this residual acid, but these were of a basic character, anci could not be obtained in a pure state, but in composition they approximated to basic lead glycerates. The nature of this residual acid is further discussed in the following communica- tion. As regards the other above-mentioned products, the following quantities were obtained, in each case froin 60 grams of calcium glycerate, ( C3H5O4j2Ca,20H2:-Total volatile acetic acid. I I I .. . .. , . . . 1.711 gram 6.065 grams 1-067 gram 7.456 grams 11 . .. . . . . . . (lost) S-lS’l ,, 0.985 ,, 7 *472 ,,I11 . * . . . , . .. (0 ”71 gram) (3 -694 ,, ) (iJ.0806 ,, ) (3-799 ,, )IV . .. .. .. ,. 1 299 ,, 7.00 ,, 0.132 ,, 7.198 ,, About one-half of‘ the fermented liquid was lost in Expt. 111,so that no value attaches to the absolute amounts found, but the ratio of alcohol to acids remained undisturbed hy the loss. Tbe proportion of alcohol tG acetic acid in Fermentations 111 and IV, in which butJ little formic acid was produced, is respectively 174 Dermentation 111. .. Alcohol . Acetic acid :: 1: 5.35 9, 9IV.... 7, 1 : 5.54 This relationship corresponds approximately to 1m01. of alcohol to 4 mols. of acetic acid :-CzH60H:4(OH&OOH) = 46 : 240 = 1: 5.2. The authors provisionally suggest the following as the equation according to which the glyceric acid undergoes this decomposition :-5CSHC04 = CZHGO + 4CzH402 + OH, + 5co2 + 3H2.This equation not only indicates the molecular relationship between the alcohol and acetic acid formed, but is also faidy in accordance with the proportions of these substances obtained in the decomposi- tion of a given weight of glyceric acid. 101. "An optically active glyceric acid." By Percy F. Frankland, Ph.D., and William Frew, University College, Dundee, St. Andrews University. The residual non-volatile acid referred to in the previous note is shown to be of the two oppositely active forms of which, according to Van't Hoff's theory, ordinary inactive glyceric acid is composed. by repeating the experiments on a much larger scale, the authors have succeeded in obtaining the calcium salt in the form of beautiful, transparent and colourless, prismatic crystals, whilst ordinary calcium glycerate is only obtainable as an indistinctly crystalline, granular mass.The specific rotation at 14.4"C. in a solution containing 10 grams salt in 100 C.C. was found to be [a]== -12.09. Great difficulty was encountered in obtaining the specific rotation of the acid, in consequence of the tendency to anhydride-formation during the evaporation of its solutions. By decomposing a quantity of thc calcium salt, corresponding to 2 grams glyceric acid, with oxalic acid and filtering, a specific rotation at 12" C. in a solution containing 2 grams in 10 C.C.of [a]== $2.14, was obtained. Thus, whilst, the acid itself is dextro-rotatory, its calcium and sodium salts are strongly laworotary.The anhydride also is strongly lsevorotary, for by heating some of the acid for six hours on the water-bath, and then taking up with water, a solution giving a rotation of -3.2" was obtained, although a large quantity of a white substance (doubtless %he anhydride) remained undissolved, so that this rotation must have been due to a small quantity only of the anhydride which had passed into solution (ordinary glyceric anhydride is said to dissolve in 646.8 parts of boiling water), so that its ltmorotatioii must be very powerful indeed. On the ohher hand, it was found that by continued digestion with water on the wat,er-bath of a solution of active glgceric acid containing anhydride, the rotation became more and more right-handed, obviously in consequence of the gradual hydration of the anhydride.Peihfectly analogous observations were made by Wisli- cetius in his well known studies on paralactic acid, for whilst this .acid also is dextrorotary, its salts and anhydride are laevorotary, the lather most powerfully so. The authors refer to experiments previously made by Lewkowitsch (Bey., 1883, 2720) to obtain the active modifications of glyceric acid, in whiclr the mould Penicillium glaucum was grown in solutions of ammonium glycerate, and these solutions were afterwards found to possess a left-handed rotation. 102. ‘‘ The a-and /%modifications of benzene hexachloride.” By F. E. Matthews, Ph.D. The author finds that benzene is readily converted into hexachloride by passing chlorine into a dilute (I per cent.) solution of sodium hydroxide having a layer of the hydrocarbon on its surface; the action takes place in the dark, and eren at the temperature of a freezing mixture, the rate of formation of the chloride depending practically only on the rate at which the chlorine is passed in.Hexachloride is also formed in presence of water alone, but it would seem that there is an advantage in using alkali, the amount of un-crystallisable products being less when it is used. The crude hexachloride is a rriixture of about $0 per cent. of the a-with about 30 per cent. of the isomeric P-hexachloride described by Mennier and Schupphaus. The author finds that the two modifica- tions may be separated by steam distillation, the a-variety alone being volatile.The pure a-hexachloride crystallises in characteristic fern leaf-like forms melting at 157”. The p-hexachloride for&s small, very brilliant crystals, and sublimes without melting ; it is much less soluble than the a-compound, but, nevertheless, it appears to be im-possible to separate the two modifications of fractional crystallisation. Determinations by Raoult’s method indicate that both It-and /?-corn- pounds are to be represented by the same molecular formula, CCH6C16. Both yield 1:2 :4-trichlorobeirzene when submitted to the action of an alcoholic solution of potassium hydroxide, the /?-compound being much less readily attasked.The author finds that bromine also acts additively in presence of dilute akali, and that additive compounds of other derivatives of benzene, &c., may be obtained by slight modificat>ions in the mode of working. 1’it; DrscussioN. Dr. ARMSTROSGthought that I)r. Matthews’s observations wcl-e of special interest and value, not only as a contribution to our knowledge of the addition compounds of benzene, but especially in relation to the theory of the formation of chlorides by the action of chlmine. In his address to the B. A. Chemical Section in 1885, he had suggested that perhaps the “induction” observed by Hunsen and Roscoe in a mixture of chlorine and hydrogen is due to the occurrence of a change in which a something is produced which then promotes action between the two gases, it being assumed that the pure gases would not interact.Subsequently, in the discussion among the members of the Electrolysis Committee, he had suggested, in reference to Pringsheim’s observations on the influence of moisture, that perhaps the initial change was one involving the production from water arid chlorine of hypochlorous acid, which would account for the expansion noticed to occur by Pringsheim supposing a gaseous hydrate of chlorine to be nffect)ed(OH;Cl, =HCl + HClO). From tbis point of view, lie had been led to try the effect of moist mercuric oxide as a chlorine “ car-rier,” and had found that it certainly promoted the action of chlorine and bromine. Dr. Matthews’s observations appeared in like manrier to show that hypochlorous acid plapod an important part in chlorina- tion.With regard to the constitution of the two hexachlorides, the evidence that both were symmetrical appeared by no means con-clusive ; it was not at all improbable that in one two chlorine atoms were associated with the same carbon atom. Mr. CRCGSsaid that the action of hypochlorous acid on benzene was deserving of much further study. Wish the object of irivesti- gating the pheiiose described by Carius, lie had devoted considerable time to the investigation, but hitherto unsuccessfully. Dr. COLEMAX~drew attention to inositoi, the hexhydroxj-compound corresponding to benzene hexachloride. Four modifications of this compound were now known, two of which were optically active.These facts pointed to geometric isomerism as an explanation of thc differences in constitution. Dr. MATTHEM’Sthought that under the conditions under which the hexachlorides were formed in his experimeuts it was very unlikely that intramolecular change should take place, such as would be involved in the formation of a compound containing two chlorine atoms attached to one carbon atom. He also thought that, taking Jungfleisch’s observations on the formation of chlorides of chloro-benzenes into account, it was improbable that either hexaciiloride had an unsymmetrical constitution. 103. “The molecular volumes of the satupated vapours of benzene and of its haloid derivatives.” By Sydney Young, D.Sc.The author has already shown (Trans., 55, 486) that when the four monohaloid derivatives of benzene are compared together at their boiling points under any equal pressure, these boiling points, expressed on the absolute scale, and also the molecular volnmes of the liquids, bear a constant ratio to each other, whatever the pressure. These results are in agreement with Van der Waals’s generalisation, according to which the above ratios should be constant at “cori-e- sponding ” pressures, which in this case are equal pressures, since the critical pressures are equal. The molecular volumes, in the liquid state, of benzene and fluor-benzene were found to bear an approximately constant ratio to each other at their boiling points under “ corresponding ” pressures.Determinations have now been made of the molecular volumes of the saturated vapours of these compounds by the method recently described to the Society. The results obtained show that the molecular volumes of the saturated vnpours of the five compounds bear an approximately constant ratio to each other at all “corre- sponding ” pressures (these pressures being again equal in the case of the halogen derivatives). Professor Orme Masson has recently pointed out (Phil. Mug., November, 1890) that the molecular volumes of the haloid derivatives of similar hydrocaybons, at their boiling points under normal pressure, bear the same ratio to each other as those boiling points, expressed on the absolute scale. In a short paper in the same number of the Phil.Mug., the author showed that Mnsson’s Jaw is really a special case of a more general one, which should be true if Van der Waals’s generalisatiocs were strictly accurate. This relation may be expressed as follows:-The molecular volumes of any two substances, both in the liquid state and as saturated vapour, at their boiling points under “corresponding ” pressures should be directly proportional to their absolute critical temperatures, and inversely proportional to their critical pressures. When the critical pressures are equal, as in the case of the halogen derivatives of benzene, and possibly also of some or all of the groups of compounds examined by Professor Masson, the relation beconies simply :-The molecular volumes, both of liquids and of saturated vapour, of any two nearly related substances whose critical pressures are equal, at their boiling points under equal pressure, are directly proportional to their absolute critical temperatures, and therefore to their (absolute) boiling points under any equal pressures. Tlie author has already show-n that this relation holds good approximately 1’7s for the liquid state, and proof is now afforded that the relation is also approximately true for the saturated vapours.With regard to the saturated vapours, the above generalisation may be stmated in the following way, which probably may be found useful :-The densities of the satorated vapours (conipared with hydrogen or air) of different substances, at their boiling points under “corresponding ” pressures bear the same ratio to their theoretical vapour densities.So far as benzene and its halogen derivatives are concerned, this relation is found to bold good approximately within wide limits of pressure. 104. ‘& Phenuvic acid.” By A. Colefax, B.A.,Ph.D. The author has compared Schloesser’s phenuvic acid with the phenylmethylfurfurancarboxylic acid of Paal, the work having been carried out at the suggestion of Professor IF’ittig ; he finds that the two acids are isomeric. He discusses the constitution of the acids, and arrives at the co’nclusion that at present the evidence is insufficient to enable any decision to be arrived at. 105. “ The action of phosphoryl trichloride on phosphorus pent- oxide.” By G.N. Huntly, Associate of the Normal School of Science. In 1871, Gustavson noticed that after prolonged heating at 200” phosphoryl trichloride and phosphorus pentoxide interacted to form an npparently homogeneous mass. A similar product having recently been obtained by the action of chlorine on phosphorous oxide (Thorpe and Tutton, Trans., 1890, p. 572), at the suggestion of Professor Thorpe the author repeated Gustavson’s experiments. The behaviour of the substance obtained towards neutral solvents and on distillation leads to the conclusions :-(1.) That there is no evidence that any compound of the composi- tion P0,Cl or (PO;Cl), exists. (2.) That the interaction of phosphoryl trichloride and phosphorus pentoxide is not represented by the equation P,O, + POCI, = 3P02C1, but is much more complex. (3.) That pyrophosphoryl chloride, P,O,Cl,, and a substance con- training chlopine and phosphorus in the ratio of 5P : 7C1 are produced in the interaction. HARRISON AND SONS, PRINTERSIN ORDINARY TO HER MAJESTY, ST. MARTIN’S LANE.
ISSN:0369-8718
DOI:10.1039/PL8900600169
出版商:RSC
年代:1890
数据来源: RSC
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