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ABSTRACTS OF THE PROCEEDINGS OF THE CHEMICAL SOCIETY. No. 39. Session 1887-88. May 19th, 1887. Mr. William Crookes, F.R.S., President, in the Chair. Messrs. S. F. Benford, Edgar Hall, J. S. Jackson and Hugh Gordon were formally admitted Fellows of the Society. Certificates were read for the first time in favour of Messrs. William Bott, Yh.D., Owens College, Manchester ; William Nathaniel Evans, 66, Stackpole Road, Bristol ; Khasberao B. Jadhara, Baroda, Bombay Presidency, India ; J. M. Kavanagh, Victoria Mill, Herbert River, North Queensland ; John T. Sheard, Gas Offices, Bloom Street, Salford ; Henry Livingstone Sulman, 13, Brewster Gardens, St. Quintin Park, W. ; Frederick Percy Watson, 31, Carholme Road, Lincoln. The following Papers were read :-46.“ The Formation of Hyponifrites.” By Professor Dunstan and T. S. Dymond. Zorn (Ber., 15,1258) has stated that alkali nitrites and nitrates are readily acted on by ferrous hydroxide, forming hyponitrite, ammonia, nitrogen and nitrous oxide. Divers and Haga (Trans., 1884, 87, and 1885, 364) allege that alkali nitrites yield much ammonia, but neither hyponitrite nor hydroxylamine, nor any gaseous product ; and that alkali nitrates are wholly unaffected ; while nitric oxide in presence of alkali is to a large extent converted into ammonia by ferrous hydroxide, but yields no hyponitrite. The authors find that nitric oxide in the absence of alkali is reduced by ferrous hydroxide to nitrous oxide and nitrogen ; no ammonia or hyponitrite is formed.In the presence of an alkali (sodium hydroxide), 74 nitric oxide is partly reduced to nitrous oxide and nitrogen, and partly absorbed ; the solution contains hyponitrite and ammonia, but on standing with excess of ferrous hydroxide it evolves nitrogen, and the hyponitrite disappears. The amount of hyponitrite formed depends within certain limits on the quantity of alkali which is present, on the quantity of ferrous hydroxide used, and on the time during which action is allowed to proceed. When three formula weights of ferrous hydroxide, Fe(OH),, and one of nitric oxide are nsed, the quantity of hyponitrite formed increases with each formula weight of sodium hydroxide that is added. About 20 per cent. of the nitric oxide may be converted into sodium hyponitrite.Alkali nitrites and ferrous hydroxide readily interact, producing nitrogen, nitrous oxide, ammonia and hyponitrite. The amounts which are formed of these substances depend on the quantity of ferrous hydroxide used, and also on the time during which the action continues. Excess of ferrous hydroxide after some time converts sodium nitrite entirely into nitrogen and ammonia. As a lecture experiment, it is recommended to dissolve 5 grams of ferrous sulphate in about 25 C.C. of water, and to precipitate the liquid with sufficient of a 10 per cent. potash or soda solution to leave the mixture faintly alkaline; 1 gram of sodium nitrite dissolved in about 25 C.C. of water is then added, and the mixture stirred.After effervescence has ceased, and the liquid has stood for about half an hour, it is filtered, If the filtrate is diluted with an equal volume of water, and carefully neut'ralised with acetic acid, on the addition of silver nitrate a pale yellow precipitate of silver hyponitrite (mixed with some silver nitrite) will be obtained. Or a few drops of a silver nitrate solution may be added to the liquid before neutralisation ; but in this case the precipitate will rapidly darken in colour. Alkali nitrates are hardly at all affected by ferrous hydroxide ; small quan- tities are slowly converted into ammonia. In explaining their results, the authors draw attention to the simultaneous formation of hyponitrite and hydroxylamine when sodium amalgam acts on dissolved sodium nitrite.They show that the ammonia is not derived from a further action of sodium amalgam on the hyponitrite, which yields only nitrogen. Similarly, ferrous hydroxide liberates nitrogen from sodium hyponitrite, but no ammonia is formed. They consider that the action of sodium amalgam on a solution of sodium nitrite is best explained by supposing that the sodium nitrite combines with two hydrogen-atoms, forming NaN( OH),. This compound may decompose, yielding hyponitrite : NaN(OH), = NaNO + H,O; or it may undergo reduction, yielding hydroxyl- amine, NaN(OH)z + 2H = NaOH + NH20H, and also ammonia and 75 nitrogen, 4NaN(OHI2 +1OH=4NaOH+N, +2NH3+4Hz0. Ferrous hydroxide, it is suggested, acts in the same way, being a substance which will combine with the hydroxyl of water when sodium nitrite is present to unite with the hydrogen.Any hydroxylamine which may be formed will at once be converted into ammonia by ferrous hydroxide. The authors find that when excess of ferrous hydroxide is used, and nitrogen and ammonia are the only products, the reac- tion takes place almost exactly in accordance with the equations (i) 4NaN02 +80H2 +8Fe(OH), =4NaN(OH)% + 8Fe(OH),; (ii) 8NaN(OH)2 +60H2 +14Fe(oH), =8NaOH +3N2 +2NH3+14Fe(OH)3. Since nitric oxide in presence of alkali yields exactly the same products as nitrites, the change can be most readily explained in the same way, assuming that the compound NaN(0H)z is first formed. 47."Ozone from Pure Oxygen." By W. A. Shenstone and J. Tudor Cundall. The authors describe an apparatus in which oxygen has been pre-pared and stored without the possibility of air gaining admittance. So far as it is possible to determine the purity of the gas by tests, it would appear certain that it has contained at. most &== of nitrogen. The oxygen has been collected and sealed up in glass tubes containing phosphoric oxide, in contact with which it has been kept for periods ranging from eight weeks to eight months. Subsequently it has been submitted to the action of electricity, and the ozone produced has been measured. In one experiment made at 10" C. no less than 11.7 per cent). of the oxygen taken was converted into ozone. This is a very considerably higher proportion than has been obtaincd either by Brodie or by the authors from ordinary oxygen when similar means of electrification are employed, but not so high as was obtained by AndPkws and Tait, who, however, worked in a different way, and the exact value of whose results is uncertain in consequence of the tendency of the sulphuric acid that they used in their gauges to absorb ozone.The action of dry ozone on dry mercury has also been studied. Dry ozone from pure oxygen is decomposed in the well-known manner by pure and dry mercury, but without visible oxidation of the mercury. Further, when a definite volume of oxygen is ozonised and afterwayds left in contact with mercury for many hours, the oxygen almost entirely recovers its original volume, the small differences observed between the initial and final olumes being pro- bably due to the difficulty of measuring oxygen with accuracy in a tube partly coated with mercury.76 The authors point out that the apparently high yield of ozone obtained under somewhat unfavourable conditions as to temperature may be due- l. To the absence of nitrogen, the presence of which Andrews has shown is, under some conditions, very unfavowable to the production of ozone. 2. To the character of the electric discharge, which is most free from large sparks when the air and glass surfaces from which the discharge takes place are free from moisture. The paper conelrides with a note on the character of the silent; discharge of electricity in ozone generators of the Siemens type, the influence of dryness on the character of the discharge being discussed.Very full details are given of hhe method they now employ for pre- paring and storing pure oxygen. The method might readily be adopted in the case of other gases that do not attack mercury. The apparatus was chiefly constructed for the production of pure gases for various other experiments on the action of electricity on gases that are still incomplet’e. 48. “The Volumetric Relat’ions of Ozone and Oxygen.” A Lecture Experiment. By W. A. Shenstone and J. Tudor Cundall. Soret and Brodie have shown that if w be the contraction produced on the electrification of a mass of oxygen, then 2u will represent the further contraction that will occur on absorbing the ozone formed by means of turpentine.If it be true that ozone completely dissolves in turpentine, this indicates that three measures of oxygen are con-cerned in the formation of two measures of ozone. The authors describe an apparatus which they have constructed for readily exhibit- ing Soret’s observation to a class. DISCUSSION. The PRESIDENTsaid that he had been accustomed to join tubes ilz situ in the manner described by Mr. Shenstone. He added that it was possible to join together two different kinds of glass by means of a little soft white enamel, such as could be obtained from Powell’s. Mr. FAIRLEVhad also joined tubes in the manner described by the authors ;calling attention to Brodie’s ozonising apparatus, he remarked that the tube used by Brodie was probably thinner than was used by the authors.Dr. ARMSTRONGthought that the results of the authors’ experiments on the action of mercury on ozone were a valuable contribution to our knowledge of the influence of minute amounts of third bodies on the coimse of chemical change. He suggested that it was important, if possible, to determine the extent to which oxidation took place in presence of varying minute amounts of moisture, in order to ascertain if this exercised an influence comparable with that exhibited in Prof. H. B. Dixon’s experiments on the rate of propagation of the explosive wave in a mixture of carbonic oxide and oxygen. Mr. SEENSTONEsaid that experiments such as were suggested by Dr.Armstrong, although very difficult with mercury, might probably be carried out with silver, which effected the decomposition of ozone with extraordinary facility. In reply to the question put by hfr. Page, he was quite unable to account for the peculiar condition assumed by the mercury when submitted to the action of the ozone. He had not been successful in joining tubes with the aid of the enamel spoken of by thepresident, but on the other hand had found it easy to join even combustion tubing to soft glass by means of an oxyhydrogen jet. 49. “On the Thermal Phenomena of Neutralisation and their bearing on the Nature of Solution and the Theory of Residual Affinity.” By S. U. Pickering.In dilute solutions the heat of neutralisation of an alkali is a con-stant quantity, independent of the nature of the alkali; and the majority of acids give the same results with any given base, whence it follows that M,E,Aq -M,’R,Aq = M,R’,Aq -M’,R’,Aq, where M and R are electropositive and electroiiegative radicles respec-tively. Each term of this equation is made up of two quantities, M,R (heat of formation of the salt molecule) and MR,Aq (true heat of dissolution of the salt), and it is impossible that such a relation- ship should exist were these actions independent of each other ; they must be part of one quantity, and as M,R is a chemical action, so also is B!tR,Aq. The affinity of M and R are not entirely saturated by their combination with each other, and it is only by the further com- bination of the compound with water that saturation becomes complete.The equation can obtain only if the water satisfies the residual affinity OP either the non-metallic or the metallic atom, and in the event of atomic valencies being whole numbers, all the terms of the equation will be equal, whereas if these valencies are not whole numbers the equation will be made up of two pairs of equal terms. The recognition of the heat evolved in any action being an absolute measure of the affinities saturated is necessitated by a study of these thermal yesults. The few cases in which acids have a higher heat of neutralisation than the majority. may be explained by their residual affinity being in excess of that which water can saturate ; while in those cases where abnormally low results are obtained the salt is probably partially dis- sociated by the water.Owing to the heat of neutralisation being independent of the nature of the base, it follows that the heat of formation in solution of similar salts of two different metals differs by a constant quantity, whatever the non-metallic radicle may be. DISCUSSION. With reference to the hypothesis submitted to the Society in 1885 by Mr. Pickering, that the valency of an atom is never a whole number, but slightly smaller or larger, Dr. ARMSTRONGremarked that it was impossible at present to put any such hypothesis to the test, owing to the complexity of the phenomena which had to be inter- preted.On the other hand, t,he hypothesis t’o which attention had been directed by Helmholtz, in the last Fnraday lecture, involved a precise and clear conception-that of a definite unit-valency, and was a necessary deduct’ion from Faraday’s law of electrolysis : in the speaker’s opinion there was as yet no other course open than to con- sider the facts in the light of this hypothesis. He was, however, entirely of Mr. Pickerhg’s opinion with regard to the interpretation to be given of the thermal values obtained on neutralising dilute solutions, having already, in fact, as Mr. Pickering had pointed out in his paper, used the same argument in reply to Dr. Nicol in the course of the discussion on the nature of solution at the meeting of the British Association at Birmingham.Dr. Nicol did not appear to have recog- nised its force, to judge from the remarks at the conclusion of his paper in the current part of the Transactions ; and disregarding the evidence afforded by the heat-evolution on dissolution of many salts- which can only be due to one cause, viz., to association of the dis- solved substance with water-claims, in support of his contention that hydrates do not exist in solution, the results of the thermal study of changes which it is almost beyond doubt are of a complex character, and which have hitherto remained uninterpreted. 50. “The Action of Metallic Alkylates on Mixtures of Ethereal Salts and Alcohols.” By T. Purdie, Ph.D., B.Sc., Professor of Chemistry in the University of St, Andrews. The author having observed (Trans., 1885, 855) that the ethylic salts of fumaric, cinnamic and oxalic acids are converted into the corresponding methylic salts by the action of a solution of sodic methylate in methylic alcohol, finds that the reaction in question is of general application : that is to say, when a mixture of an alcohol with an ethereal salt containing a different alcoholic radicle from that of the alcohol is treated with small quantities of sodic or potassic alkylhte, an interchange of radicle takes place between the alcohol and the ethereal salt; and that the chemical change exhibits in a marked degree the character of continuous action.It is supposed 79 that the reaction is effected by the continuous formation alld decom- position of a compound of the ethereal salt with the alkylate.Besides the cases mentioned above, a similar reaction is found to occur when minute quantities of alkylate are added to the following mixtures : methylic oxalate with ethylic alcohol ;amylic oxalate with ethylic or methylic alcohol ; and ethylic oxalate with amylic alcohol. Also in the case of mixtures of amylic acetate with ethylic or methylic alcohol ; ethylic acetate with amylic alcohol ; and phenylic acetate with ethylic alcohol. A series of blank experiments to which no alkylate was added was performed for purpose of comparison. While the extent of inter- change of alcoholic radicle occurring in the latter is usually small, the interchange in the former amounts under similar conditions frequently to 50 per cent., and in some instances is almost quantitatively com-plete.DIscusSION. Dr. ARMSTRONGremarked that, as Prof. Purdie had not failed to point out, the exchange of radicle occurring between the ethereal salt and the alcohol is most probably effected by the alternate pro- duction and decomposition of an additive compound formed by the union of the salt with the alkylate, in the manner suggested by him in a “ Note on the: Action of Sodic Ethylate on Ethylic Oxalate and other Ethereal Salts,” communicated to the Society in January, 1874 (Bey., 7, 129). Several applications of the principle involved in this explanation were to be found in the edition of vol.iii of Mikker’s Chemistry by Mr. Groves and himself (at pp. 861, 907, 923), and the formation of ethylic acetoacetate from ethylic acetate and sodium ethylate was there represented (p. 909) by equations identical with those recently put forward as original by Claisen and. Lowman ;whose experiments throw as much, but no more, light on the genesis of the acetoacetate as Geuther’s original experiments-a fresh proof that these last are still not rated at their proper value. It was remarkable also that it was not generally recognised that sodium ethylate, not sodium, was the effective agent in transforming ethylic salts, W. Wislicenus having, for example, in his recent paper represented the change effected by sodium in mixtures of ethylic salts as directly due to the sodium, and as involving the formation of sodium substitution-deriva-tives.The additive compound of the sodium alkylate with the ethereal salt had been represented by himself and others as an atomic compound, the assumption being made that the elements of the alkylate became distributed; it might be pointed out that it was, perhaps, unnecessary to make this assumption, it being conceivable that change would supervene if once the alkylate became associated with the ethereal salt without its elements becoming distributed. 80 ADDITIONS TO THE LIBRARY. I. Donations. United States Geological Survey : Monographs, XI : Geological History of Lake Lahontan : by J. C. Russell : Washington, 1385. from the Director of the Survey, Journal of the College of Science : Imperial University of Japan : vol.i, Part I (cont.) : Tokio, 1886: from the University. Colonial and Indian Exhibition : Reports on the Colonial Sections : Edited by H. T. Wood : London, 1887 : From the Commission of the Exhibition. United States Geological Survey : Mineral Resources of the United States, 1885 : Washington, 1886: from the Director of the Survey. The Work of the Imperial Institute : by Sir I?. A. Abel : London, 1887 : from the Author. Nitrate of Soda; its Importance and Use as a Manure : by A. Stutzer : London, 1887: from the Publisher. Cellulose: by C. a’. Cross and E. J. Bevan: edited by W. R. Hodgkinson : London, 1885 : from the Authors. Kew Commercial Plants and Drugs. No. 10: by T. Christy: London, 1887: from the Author. 11. By Purchase. Official Year Book of the Scientific and Learned Societies of Great Britain and Ireland : London, 1887. Principien der Organischen Synthese : von E. Lellrnann : Berlin, 1887. Fortschritte im Probirwesen : von C.A. Balling : Berlin, 1887. Vortrage uber die Entwicklungsgeschichte der Chemie : von A. Ladenburg: 2 ed. : Braunschweig, 1887. RESEARCH FUND. A meeting of the Research Fund Committee will be held in June. Fellows desiring grants are requested to make application before June 11th. HABRISON AND SONS, PRIBTEBS IN OBDINAltY TO HXIL MAJESTY, ST.MAUTIN’S UXE,

ISSN:0369-8718    

DOI:10.1039/PL8870300073

出版商:RSC    

年代:1887

数据来源: RSC