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Abstracts of the Proceedings of the Chemical Society, Vol. 3, No. 33 |
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Proceedings of the Chemical Society, London,
Volume 3,
Issue 33,
1887,
Page 19-28
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摘要:
ABSTRACTS OF THE PROCEEDINGS OB THE CHEMICAL SOCIETY. ~ No. 33. Session 1886-87. February 17th, 1887. Dr. Hugo Muller, F.R.S., President, in the Chair. Messrs. E. Hori and Charles E. Sohn, Jun., were formally admitted Fellows of the Society. Certificates were read for the first time in favour of Messrs. Harold Govett Colman, Owens College, Manchester ;James Tudor Cundall, Dale Side, Hampton Redland, Bristol ;Alfred John Evans, B.A., Sheegorah House, Boyle, Ireland ; Arthur Harden, Ashville, Upper Charlton Road, Manchester ; William Houlding, Stanley House, Anfield, Liverpool ; Theophilus Horne Redwood, 154, Lad-broke Grove Road, W. ;George Robertson, Madeira Villa, Woodford, Essex; W. Harry Stanger, 23, Queen Anne’s Gate; Patrick T. O’Sullivan, 57, Great Britain Street, Cork.It was announced that the following changes in the Council List were proposed by the Council:- As President; Mr. W. Crookes, F.R.S., vice Dr. Hugo Muller, F.R.S. As Vice-presidents : Professor McLeod, F.R.S., Professor Schor-lemmer, F.R.S., and Mr. Ludwig Mond, vice Mr. Crookes, F.R.S., Professor Liveing, F.R.S., and Professor T. E. Thorpe, F.R.S. As Ordinary Members of the Council: Professor A. H. Church, Dr. P. F. Frankland, Professor Kinch and Dr. H. F. Morley, vice Messrs. H. T. Brown, A. E. Fletcher, and Professors illeldola and Pickering. Messrs. C. W. Heaton, P.I!. Frankland and Wyndhain Dunstan mere appointed by the meeting to audit the Treasurer’s accounts. The following papers were read :- 20 11.'' The Influence of Temperature on the Heat of Dissolution of Salts." By S. U. Pickering. This is an extension of the anthor's previous work on the sulphates -entitled " The Influence of Temperature on the Heat of Chemical Combination " (Trans., 1886, 260)-which tended to show that the heat of dissolution of a salt does not increase regularly with a rise of temperature, but that irregularities occur at various points, so that the heat of dissolution must be represented by a series of curves. The experiment,s with potassium sulphate, hydrated and anhydrous magnesium sulphate and hydrated and anhydrous copper sulphate have been repeated, and the investigation extended to potassium, sodium, hydrated and anhydrons strontium chloride, potassium and the two strontiuin nitrates, the two sodium carbonates, sodium acetate and potassium sodium tartrate.The investigation com-prises over 700 determinations, the mean results with each salt being deduced from two to five distinct series of experiments, each performed with diflerent thermometers. The observations extended from 3" to 25". In all cases it was found that the irregularities previously noticed were the result of error, and that the hsat of dissolution of a salt is represented by a aeries of straight lines. In rising from low temperatures the heat of dissolution is expressed by a straight line up to a certain point, when the rate becomes suddenly lowered and remains constant till a further sudden reduction occurs at some still higher temperature.The average divergence of all the mean results from lines of perfect straightness amounted to less than one-thousandth of a degree. With the normally anhydrous salts one lowering OF the rate (atnounting to about, 30 per cent.) only was observed between 3" and 25"' occurring at temperatures between 14" and 9.5" in the various cases ; while with the salts which combined with water of crysti-tllisa-tion the first alteration occurred at temperatures between 9" and 7", and a, second change took place at 21" to 18": the frequency as well as the temperature of occurrence appearicg to depend mainly on the tendency of the salt to combine with water. This lowering of the rate o€ increase in the heat of dissolution as the temperature rises must be accompanied by an increase in the specific heat of the solu-tion which would indicate decomposition of some description.Marignac's determinations of the specific heat of solutions give a rate of increase agreeing very closely with the author's results, and they also show that a further lowering takes place at temperatures above 25" up to 50". Tilden's direct determinations of this rate at the higher temperatures show a very much larger decrease in the rate, but they cannot be frtzely accepted, as they are entirely at 21 variance, not only with all specific heat determinations, but also with a fundamental principle of thermochemistry. The heat of combination of a salt with its water of crystallisation is deduced from the author’s results.He concludes that it is not a constant quantity at all temperatures ; the general effect of rise of temperature being to diminish it, although at very low temperatures this effect seems to be more than counterbalanced by some other cause, probably the tendency of the water molecules to unite with each other, the heat of combinstion diminishing then with fall of temperature. The more water a salt contains the more marked arc both these results. DISCUSSION. Dr. ALDERWRIGHTthought that the Society was to be con-gratulated on the fact that one of its members had undertaken the laborious and delicate work involved in making accurate thermo-chemical determinations of heats of dissolution, and in avoiding the numerous sources of error which attend such valuations.He found it somewhat dificult to realise the practicability of obtaining exactitude of such an order that the experimental errors should not exceed two or three calories, which apparently Professor Pickering claimed to have done. Julius Thornsen, in his most accurate and painstaking researches, generally found a minimum variation from the mean in consecutive observations of from 5 to 10 calories; and Dr. Alder Wright himself, whilst working on the heat of dilution of con-centrated solutions (with, however, less complete appliances than those used by Thomsen),found that about 10 calories was the minimum experimental error attaching to each separate valuation, The question of the amount of the experimental error seriously affected Professor Pickering’s conclusion that the curves indicating his results frequently consisted of two or more straight lines making an angle or sudden break in the curve; it would seem far more probable, d priori, and in view of the general course of physioal phe- nomena, in which some value is a function of the temperature, that the curve is truly a curve throughout, expressible by some such symbols as 1 + act + pi?, where /3 may be + or -. Judging from some of Professor Pickei-ing’s diagrams, the deviations exhibited by some of his observations from the sets of straight lines deduced by him as mean results, are as great as, if not greater than, the deviations which they would exhibit from a mean curre of this kind ; and until it had been shown that the deviations in this latter case were mate- rially wider than could be accounted for by the degree of magnitude of the experimental errors, whilst in the former case this was not so (which so far Professor Pickering had not done), he should feel 22 some degree of difficulty in accepting the conclusion that the curves are not regular ones, but are portions of the bounding circumferences of irregular polygons.[Professor TILDENwrites, with reference to the statement made by Mr. Pickering that he had used too little water in his experiments on the heat of dissolution of potassium sulphate, and that the salt could not have been all dissolved : that in every experiment of which the results were quoted in his paper the salt was entirely dissolved.J 12. " Periodates." By C. W. Kimmins, D.Sc., B.A. (Contribu-tion No. IX from the Laboratory of Gonville and Caius College, Cambridge). The author, at the suggestion of Mr. Pattison Muir, has re-examined certain periodates of potassium, silver and sodium, with the object of explaining the discordant results of Tarious observers. Besides the Ralt N%H,IO,, described by Langlois, he has obtained a sodium periodate of the formula Na3H2106;he also describes a potassium periodate K3H120g. He has prepared and analysed the following silver salts :-Ag2HI05,dark brown. AgI04,bright yellow. light yellow. AgzH,Io6,dark red. Ag4I2O9*30Hz, claret-coloured.AgyH210s,slate-coloured. Ag41209-OH2, orangs.Ag4I2Og,chocolate-coloured.AgIOa*OH2, 13. '' Sulphonic Acids derived from the 6-Monohaloid-derivatives of Naphthalene." By Henry E. Armsfrong and W. P. Wynne, B.Sc. Experiment having shown that the sulphonic acids obtained from naphthalene under conditions by which the occurrence of secondary change-which undoubtedly takes place when sulphuric acid is used as a sulphonat.ing agent-is avoided, differ from those formed by means of sulphuric acid ; and that the a-monohaloid derivatives of naphthalene yield isomeric sulphonic acids : it became desirable to study the behaviour of the P-monohaloid derivatives. By the action of fuming sulphuric acid at 130-140" on P-chloro-naphthalene, Arne11 (BUZZ.. Xoc. Chim,, 45, 184) has obtained two isomeric acids: one of these yields a sulphochloride melting at 129", which is converted into 6-dichloronaphthalene by distillation with PCl,; the sulphochloride of the isomeride melts at 109" and yields E-dichloronap hthalene .By acting with S03HC1 on p-chloronaphthalene in molecular proportions, the authors have also obtained two isomeric acids, which ;we undoubtedly identical with those discovered by Amell. Tho l~ariumsalt of the chief product, (CloH6C1~SO3),Ba*4H,0,crystallises in lamin= ; the potassium salt, CloH,C1-SOgK + HzO, crystallises in small scales. The isomeric salts, (C,oH,C1*S03),Ba and C,,,H,Cl*SO,K.~H,O, are much less soluble in water. p-Bromonaphthalene, in like manner, yields two isomeric acids.The barium salt of the chief product, [C10HGBr*S03]2Ba-3+H20,and the potassium salt, CloH6Br*S03K*1~Hz0, crystallise in thin octagonal scales. The corresponding salts of the isomeric acid are anhydrous and very sparingly soluble in water ; the barium salt crystallises in tufts of flat needles, the potassium salt in thin lustrous laminae. p-Iodonaphthalene also yields two isomeric acids. The barium salt of the chief product, [CloH6I*SO3],Ba.4!jH,O, and the potassium salt, CloH61*S03K*H20,crystallise in thin hexagonal scales. The salts of the isomeric acid are very sparingly soluble in water : the lead salt, [c,oH61*so3],Pb*2~H,o,crystallises in scales ; the barium salt, [C,oH61*S03]2Ba*2H20,in white flat needles ; and the potassium salt, OloH61*S03K-Hz0,in well-defined laminae.Inasmuch as the action takes place between theoretical quantities of the reacting bodies, there can be little doubt that the products result from primary changes : a very small proportion, however-at most 3 or 4 per cent.-of the haloid compound, is converted into the acid yielding the less soluble salts. Sssuming, as is probable, that the products from chloro-, bromo- and iodonaphthalene correspond in composition, the proof of the production of edi-derivatives in this manner is of considerable theoretical importance : although not absolutely placed beyond doubt, there is every reason to believe that e-dichloronaphthalene is the symmetrical heteronucleal /?2/33’-derivative; and the formation of such derivatives affords a clear indication of the existence of what one of the authors has termed a plane of symmetry in the naphthalene molecule, corresponding to a diagonal passing through two p-positions in the two nuclei of the naphthalene symbol, a, more convincing proof of which perhaps is afforded by the complete conversion of /3-naphthyl sulphate on heating at, 100” into p-napthol- 6-sulphonic acid, which is also an e-di-derivative (Bey., 15,203). 14.“ The Decomposition of Potassium Chlorate and Perchlorate by Heat.’’ By Frank L. Teed, D.Sc. The results published in the paper on this subject by Dr. P. F. Frankland and Mr. J. Dingwall in No. 32 of these Proceedings, as far as they go, entirely confirm certain results obtained by me and announced in two papers, abstracts of which appeared in the “Proceedings” Nos. 12 and 16 of the Session 1885-86.24 In my latter. paper I say that when the salt is very gently heated, the decomposition more nearly approximates to the equation 22KC103 = 14KC104 + 8KC1 + 502, to which Frankland and Dingwall make no reference, the majority of the results failing within the limits of this equation and of the equation 10KC103 = 6KC104 + 4KC1 $-302. On adding these two equations together and reducing to the lowest terms, the Frankland-Dingwall eqlnation is obtained, which is merely one of the many equations that could be formed to express in%ermediate stages of decomposition. There seems to be an idea among certain chemists that the deter- mination of the evolved oxygen and of the potassium chloride are insu6cienf data from which to construct an equation, and that it is necessary to directly determine the perchlorate formed; or at all events, the undecomposed chlorate. This idea is erroneous, because it is obvious that for every 74.5 parts of KC1 formed there mnst have been 122-5 of KC10, decomposed; and of the resulting 48 parts of oxygen, what is not evolved in the free state must have gone to form perchlorate.Any determinations of the KC10, and KCIOa are therefore unnecessary. To give the results in my second paper (the paper wa8 riot published and the data do not appear in the abstract). KC10, Oxygen KC1 Amount of taken, evolved, formed, oxygen to NO.grams. per cent. per cen& 74'5 of KCl. 1 ...... 4.3782 3.60 11-58 23.16 2 ...... 6.865 1.27 4.73 20.00 3 ...... 9.291 1.61 6-00 19.99 4 ...... 4.759 1.60 6-14 1941 5 ...... 4.4905 1.47 4.84 2263 6 ...... 6.050 0.80 2.18 27.34 I heated more gently and carefully than Frankland and Dingwall, and so obtained a higher yield of perchlorate and less free oxygen than they appear to have done. The equation 22KC103= 14KC10, + 8KC1 + 502demands 20 parts of oxygen to 74.5 of KCl. I was very careful to point out in my former paper that no equation represents the decomposition of potassium chlorate, and only proposed the two I have submitted as marking the usual limits of the final prodncts. The results with perchlorate given in my second paper were :- 25 NO.1 ...... KC104 taken, grains. 2.4355 Oxygen lost, per cent. 3.10 KCl foymed, per cent. 2.97 Amount of oxygen to 74-5 KCl. 77.76 2 ...... 3.8825 4.47 4-41 75.59 3 ...... 1.850 7.30 7.82 69.55 4 ...... 1,217 35.21 40.33 65.04 Frankland and Dingwall have failed to notice the first, high ratio of oxygen to KC1, by again driving off too much oxygen, and to this extent their results are incomplete. It is obvious that perchlorate of potassium, when it loses more oxygen than expressed by the equation KC104 = KC1 + 202, must be forming a lower oxide of potassium chloride ;and the only such oxide possible under the circumstances is the chlorate. Hence the necessity for determining the chlorate formed disappears.DISCUSSION. FRANKLANDDr. PERCY said that he regretted Dr. Teed was not present at the reading of his and Mr. Dingwall's paper, for he would then have clearly understood that they had in no way arrogated to themselves the originality of the experiments, which undoubtedly belonged to Dr. Teed. Their experiments had been made with the view of testing the correctness of Dr. Teed's results, and they had endeavoured to place these results beyond the possibility of doubt, not only by taking special precautions in the method of decomposing the salts, but also by actually determining the proportion of chlorate formed in the decnmposition of perchlorate, and the proportion of perchlorate in the decomposition of chlorate.15. "The Formation of Ethylic Cyanacetoacetate." By Dr. J. Wi1liam James, University College, Cardiff. If 50 grams (1 mol. proportion) of ethylic monochloracetoacetate be mixed with 40 grams (2 mol. proportions) of potassium cyanide, and 600 C.C. of 99i per cent. alcohol, a reaction takes place slowly at the ordinary temperature, the product consisting of ethylic potassium cyanacetoacetate, CH,(CN)-CO*CHK*COOEt. If an aqueous solution of this salt be acidified with dilute chlor- hydric acid, ethylic cya,nacetoacstate separates as a colourless oil, which solidities, if cooled, to a mass of fine silky needles, melting at 26.5" C. It cannot be distilled under ordinary pressure. Ethylic dichloracetoacetitte and potassium cyanide interact under the same conditions in a totally different manner, forming potassium dichloracetatu and ethylic acetate.16. “ The Relation of Diazobenzene Anilide to Amidoazobenzene.” By R. J. Friswell and A. G. Green. In a previous communication to the Society (Trans., 1885, 917) we have attempted to give a partial explanation of the manner in which the isomeric change of diazobenzene anilide into amidoazo- benzene takes place. We have shown that, in a,ll probabilit,y, previous to the conversion, a resolution of the molecule of the anilide into dinzobenxene and aniline is brought about by the acid present, and that these bodies then reunite in a different manner to form amido- azobenzene. Further than this we could not go, for it still appeared to us a mystery how it was possible that the anilide could be formed under conditions which ultimately lead to its resolution and recombination in a new form, for example, when 1 mol.proportion of HC1 is present. This last difficulty has been cleared away by the suggestions lately put forward by 0. Wallach (AnmaZen, 235,233), and the whole reaction now appears perfectly clear and straightforward. Diazobenzene combines with aniline at once when no excess of mineral acid is present to form diazobenzene anilide; the presence of free mineral acid, however, lessens the tendency to displacement of the amidogen hydrogen, and thus prevents (more or less completely according to the quantity of acid present) the formation of the anilide : under these condihions the tardier tendency to displacement of the para-hydrogen of the nucleus now comes into play and amido- azobenzene is very sZowZy formed. If only 1 mol.proportion of HC1 is present, the anilidc is formed, but not quantitatively, the acid though not sufficient to entirely counterbalance the tendency to dis- placement in the NH,, yet keeps apart a certain quantity of the diazobenzene and aniline, which in course of time interact to form amidoazobenzene and are consequently removed. The conditions are thus altered, and equilibrium is again established by the resolution of a further quantity of the anilide, the constituents of which slowly combine as before to produce amidoazobenzene. In this way the whole of the anilide is slowly resolved and the products recombined to form the compound, which, although the most stable under the conditions, requires a considerable time for its production, thus allowing of the intermediate production of a more quickly formed but less fitable body.87 17. “Note on Wallach’s Explanation of the Isomeric Transforma- tion of Diazoamidobenzene iiito Amidoazobenzene.” By R. Meldola, F.R.S. In a recent paper published by Wallach (AnnaZen, 235,233), that author, who has contributed such valuable results to the chemistry of the azo-and diazo-compounds, puts forward an explanation of the transformation of diazoamido-into amidoazobenzene, which seems to me to call for some comment. Ishould have been unwilling to callin question any opinion emanating from such a well-known authority had it not been for the somewhat dogmatic statement,-that in the opinion of the writer the question now appeared to have received its final dismissal (‘Lihre endgiiltiye Erlediyuy ”).AS such a statement is calculated to induce a feeling of false security on the part of those who have paid attention this most interesting case of isomeric change, I take the opportunit#yof putting upon recordmy own convictiou that the explanation advanced does not materially contribute to the solu-tion of the problem. According to Wallach’s view the reason why amidoazobenzene is not formed as the first product is because the aniline upon which the diazo-salt acts is for the most part free, i.e., its NH2-group is not saturated, and the diaeobenzene residue can therefore readily enter the group in place of one H-atom.But when the diazoamido-compound is in presence of excess of acid (or of easily decomposable salts) it becomes resolved into its constituents, and these then reunite in a different way, because the NH,-group is saturated and the diazobenzene residue prefers entering the nucleus (in the para-position). The aniline salt is in this case, according to the author, in the same condition as a tertiary amine or a phenol. A little consideration will, however, show that the known facts will not bear this interpretation, for diazoamidobenzene is a7ways the first product whenever diazobenzene chloride acts upon any mixture of aniline and aniline hydrochloride, and this shows a distinct preference for the amido-hydrogen of the free aniline to be first displaced.In tile presence of aniline hydrochloride, on the view that bhe acid of this salt decomposes the diazoamido-compound into its constituents, we have therefore a mixture of diazobenzene chloride, aniline hydro- chloride and free aniline ; Le., the coriditions are precisely the same 8,s at the commencement of the experiment. Why under these repro-duced conditions the diazobenzene chloride should now prefer attack- ing the para-H-atom of the aniline hydrochloride instead of the amid0-H of the aniline, remains, after the proposed “ explailation,” as great a mjstery as ever. 28 ADDITIONS TO THE LIBRARY. I. Doizations.Calendar of the Pharmaceutical Society of Great Britain, 1887: from the Society. Synoptic Tables of Chemistry: by A. E. Fourcroy: Translated by W. Nicholson : London, 1801: from J. Marshall, Esq., F.K.C.S. List of Fellows, Members, Licentiates, and Extr a-licentiates of the Royal College of Physicians : London, 1887: from the Council. Calendar of the Imperial University of Japan, 1886-87 : Tokio, 1887 : from the University. Quantitative Chemical Analysis : by C. R. Fresenius : Translated by f. Lloyd Bullock : 5th ed. : London, 1859; Laboratory Guide : by A. H. Church : 3rd ed. : London, 1874; Sanitary Examination of Air, Water, and Food: by C. B. Fox: London, 1878; Qualitative Chemical Analysis : by W. G. Valentin : Revised by W.R. Hodgkinson : 5th ed. : London, 1880: from W. T. Bayne, Esq. 11. By Purchase. Chemistry of the Sun : by J. Norman Lockyer : London, 1887. L’Aluminium: Par H. St.-Claire Deville : Paris, 1839. At the next meeting *on March 3rd there will be a ballot for the election of F~llo~vs,and the following papers will be read:-“The Colozlring Matter of Drosera Whittakeri.” By Professor E. H. Rennie, D.Sc. ‘‘ Anhydracetonebenzil.” By F. R. Japp, F.R.S., and Cosaio Jnnes Burton, B.Sc. “ Condensation of Benzil with Ketones.” By the same. “Constitution of Glycosine.” By F. R. Japp, F.R.S., and E. Cleminshaw, M.A. “ Diphenylglyoxaline and its Homologues.” By F. R. Japp, F.R.S. “Dehydracetic Acid.” By Dr. W. H. Perkin, Junr. HARRISON AXD SONS, PRINTERS IN ORDINAEY TO HER MAJESTY, ST.MARTIN’S LANE.
ISSN:0369-8718
DOI:10.1039/PL8870300019
出版商:RSC
年代:1887
数据来源: RSC
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