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Proceedings of the Chemical Society, Vol. 19, No. 267 |
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Proceedings of the Chemical Society, London,
Volume 19,
Issue 267,
1903,
Page 139-154
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?§sued 29/5/03 PROCEEDINGS OF CHEMICAL SOCIETY. VOl. 19. No. 267. Wednesday, May 20th, 1909. Professor W. A. TILDEN,D.Sc., F.R.S., President, in the Chair. Mr. Francis Watts was formally admitted a Fellow of the Society. Certificates were read for the first time in favour of Messrs. : Colin NoeI Bennett, 95, High Street, C‘amden Town, N.W. William Hunter Gandy, Bradley Court, Mitcheldean, Gloucester. John Howard Linday, Eenton Hall, Great Fenton, Stoke-on-Trent. Arthur Moore, 83, Elgin Road, Seven Kings, Essex. Thomas Rhind, M.R.C.S., 69, Gloucester Road, Regent’s Park. Charles J. Smith, (L Sunnydale,” Walton New Road, Stockton Heath. Sidney €3. Woolhouse, M.A., 2, Durham Itoad, Lower Edmonton, N. THE DALTON CENTENARY. The PRESIDENTstated that,, in company with Sir Henry Roscoe and Dr.T. E. Thorpe, Past-Presidents, Professor Frankland, Vice-president, Dr. Scott, Senior Secretary, and Sir TNiIliam Kamsay, Foreign Secretary, 140 delegates appointed by the Council, he had taken part in the celebra- tion by the Literary and Philosophical Society of Manchester of the centenary of the enunciation of the Atomic Theory by John Dalton, and in the name of the Chemical Society had presented the follow- ing address : THE CHEMICAL SOCIETY TO THE LITERARY AND PHILOSOPHICAL SOCIETY OF RIANCHESTER. GREETING. Recognising the Atomic Theory as having been the foundation of scientific chemistry, the Chemical Society desires to be associated with the Literary and Philosophical Society of Bfanehester in cele-brating the centenary of its enunciation by JOHN DALTON.The century which has elapsed since the recognition of the great generalisations. which led to the establishment of the theory h is afforded continuous proof of its importance throughout the whole domain of physical science, and especially of chemistry, every new development of which has served to consolidate its position. The Chemical Society offers at the same time to the Literary and Philosophical Society, so much older than itself, an expression of hearty congratulations on having been the medium of the first publication of that theory to the world, and having for upwards of a century so honorably assisted in promoting scientific, literary, and philosophical inquiry, more especially in those early days before the time of Dalton, when the physical sciences were still unorganised and waiting for the firm and philosophical basis on which they now rest.Signed on behalf of the Chemical Society, WILLTAM A. TILDEN, President. HORACE T. BROWN, T!reasurer. ALEXANDER SCOTTSEAL. W, PALMER WYNNE }Xecrelal.ies, WILLIAM RAISISA Y, Foreiyia Xewetcwg. mu9 7th, 1903. He reminded the Society that John Dalton mas born in 1766, and was therefore a young man when, in 1803, he communicated to the 141 Literary and Philosophical Society a paper ‘‘ On the Absorption of Gases by Water and other Liquids,” to which is appended the first table of atomic weights. Dalton states in the preface to his Chemical Philosophy,” that n brief outline of his views and of the results of his experiments ‘‘ was first publicly given in the ensuing minter in a course of lectures on natural philosophy at the Royal Institution in London.” The first volume of the Natural Philosophy,” containing the well-known symbols of the atoms devised by Dalton, is dated 1808.The President further announced that a bust of Dalton had been modelled with the aid of the Chantrey marble and various authentic portraits, one of which, a daguerreotype, is in the possession of the Society, and that the bust when finished would be offered to the Society, probably before the end of the session, by our Past-President, 11s. Thorpe. CEN‘L‘ENARY OF THE BIRTH OF LIEBIG.The PRESIDENTthen stated that he had a further agreeable announcement to make. The bust of Liebig which was placed on the table is a gift which the Society owes to the generosity of our Fellow, Dr. Messel. It was probably not generally known that this year, and nearly at this time, is the hundredth anniversary of the birth of the famous German chemist. The day of the month is usually stated to be May 12th, and this is the date given in Hofmann’s lecture, delivered before the Society in 1875, and is therefore probably correct. No time has therefore been lost in honouring this important event. We in England should be among the first to acknowledge the debt which science and the world at large owes to Liebig. Sixty years ago, when at the height of his fame, he visited England, and although it is true that he found but little science in this country, he had many admirers here who assisted in promoting a knowledge of the principles of plant and animal physiology which had been so largely the product of his own researches.With the advance of time has come so much new knowledge that Liebig’s teaching in connection with agriculture, physiology, and medicine seems now to be less influential than it was fifty years ago. We cannot, however, forget that his views represented at that time an immense stride in advance of the state of ignorance which previously prevailed. As chemists, we more especially recognise our indebtedness to Liebig not only as one of the chief founders of modern organic chemistry, but as having given us the system of practical instruction which, in principle, has 142 been adopted in all universities and chemical schools since his time. Whether any of the students who worked under his direction in the laboratory at Giessen still survive is uncertain, but those who went forth as teachers certainly transmitted to succeeding generations some- thing of the spirit which animated all those who came under Liebig's influence.Of the following papers, those marked * were read : *73. ''The conditions of decomposition of ammonium nitrite." ByV. H. Veley. The decomposition of ammonium nitrite into nitrogen and water proceeds according to the general lam, logA/A -x =a6, whether the reaction follows its normal course or is accelerated by the addition of another substance.The decomposition is either impeded or stopped by ammonia liberated in the solution by the addition of a metallic oxide, this effect being likewise produced by aliphatic, benzenoid, and pyridine amines, also by aromatic hydrazines, and to a less degree by oximes ;it is temporarily accelerated by amides of the aliphatic series, but other amides are ineffective. Benzoic sulphinide (I' siccharin ")7 the only imide tried, produces a considerable acceleration, but the reaction proceeds according to the general law. It does not appear that solations of ammonium nitrite, prepared from silver nitrite and ammonium chloride, become alkaline in the course of the decomposition.Incidentally it was shown that finely-divided barium sulphate, although producing no permanent elfect when added to a solution of ammonium nitrite evolving nitrogen, nevertheless temporarily increased the rate of evolution of nitrogen, owing ta some alteration in the amount of dissolved gas. DISCUSSION. Dr. DIVERSthought from the results of the investigation by Dr. Haga and himself of the interaction of sulphurous and nitrous acids in presence of bases that it was free nitrous acid which, by its action on ammonium nitrite or ammonia, gave rise to the product'ion of nitrogen. Dr. LAPWORTHsaid that Dr. Veley's observations recalled the work of Hantzsch and Schumann, who had shown (Bey., 1899, 32, 1691) that the velocity with which dinzotisation of aromatic amines takes place is accelerated by an excess of acid.This change is not,, as 143 nsually represented, a decornposition of the nitrite of the base, but is the effect of free nitrous acid on the substituted ammonium salt, or, in other words, the result of the interaction of the substituted ammonium ions with un-ionised nitrous acid. Dr. VELEYagreed with Dr. Divers that the initial change in the decomposition of ammonium nitrite was the resolution of the salt into its constituent base and acid, as is also the case with ammonium nitrate. The nitrogen or nitrous oxide resulted from a subsequent interaction of the liberated ammonia with the nitrous or nitric acid respectively. V4. “Freezing point curves for some binary mixtures of organic substances, chiefly phenols and amines.” By J.C. Philip. When the initial freezing points of a series of mixtures of two siibtances are determined and these temperatures are plotted against concentration, a freezing point curve is obtained which, in the simplest caqe, consists of two branches, starting from the freezing points of the constituents and cutting each other at a eutectic point, If, how-ever, the two substances can unite to form a compound, the two branches are cut by another intermediate curve, which may sometimes have a summit. Examples of the latter type ot curve with an intermediate branch have been found by the author for the system phenol-urea, where the summit occurs with a mixture containing 33 molecular per cent.of urea, and for the systems p-cresol-aniline, phenol-a-naphthylamine, phenol-p-toluidine, a-naphthol-p-toluidine, phenol-picric acid, in a1 1 of which cases the summit occurs when the compounds are in mclecular proportion. According to Roozeboom’s theory, the summit of the intermediate branch is reached with a mixture corresponding in composition with the formula of the compound, and crystals of this compound separate from all mixtures falling within the limits of the intermediate branch. This view has been confirmed in the above cases by analysis of the crystals which separated when solidification began. In the freezing point curve for phenol-urea, the intermediate branch is cut abruptly at the summit by another branch ending, apparently, at the freezing point of urea.Perhaps the most interesting freezing point curve obtained was that for phenol-p-toluidine, inasmuch as the compound formed by these two substances exists in two modifications with an intermediate branch on the freezing point curve corresponding with each variety. The compound of phenol and a-naphthylamine crystallises so slowly that it was found possible to realise considerable 144 portions of the ordinary branches of the freezing point curve under- neath the intermediate branch and below the eutectic temperahures. The compounds of p-cresol and aniline (plates; f. p. 21°), phenol and p-toluidine (plates ;f. p. 29O), a-naphthol and p-toluidine (needles ; f. p. 53*5O), phenol and picric acid (bright yellow needles ;f.p. S3O) have not been previously described. DISCUSSION. Dr. LOWRYreferred to the melting point curves for mixtures of water with succinic and phtbalic anhydrides recently plotted by van der Stadt (Zeit.physikcd. Clmn., 1902, 41, 353). In these cases, the ‘‘ compound” (that is,the acid) is much more stable and less fusible than its components, so that these only separate from the fused product when this consists of almost pure water or pure anhydride; the central portion of the curve thus extends from about 0 up to 96 or 98 molecular per cent. of anhydride. IRloreover, the extent to which the “compound ” dissociates on fusion can be gauged from the form of the central portion of the curve ; if there wero no dissociation, this would consist uf two intersecting lines, but if there is much dis- sociation the pointed crest becomes replaced by a rounded summit, and in extreme cases may even be reduced to a broad, fl:tttened convexity, Ah. CROMPTONinquired whether the author had ascertained to what extent his l*esults mere in agreement with the Schroeder-Le Chatelier formula.Dr. DESCHreferred to the interest which the author’s results pre- sented in connection with the study of metallic alloys, and inquired whether, in the cases examined, the descending and ascending branches of the freezing point curve were represented by straight lines. In the majority of alloys, these branches are more or less curved, indicating the formation of solid solutions, even if only to a limited extent.Dr. PHILIP,in reply, said that the freezing point curve for the system, acid anhydride-water, which had an intermediate summit at a temperature far above the freezing points of the constituents, resembled those of the systems, mercury-sodium and a-naphthol-picric acid, studied by Kurnakoff and Kuriloff respectively. He had not attempted to apply the Schroeder-Le Chatelier formula to his results, as the subject had been treated entirely from the experimental point of view. The branches of the freezing point curve, starting from the freezing points of the components, although sometimes very nearly rectilinear, were, in the majority of cases, slightly concave to the concentration axis.75. ''Isomeric partially racemic salts containing quinquevalent nitrogen. Part XI. Derivatives of dl-methylhydrindamine and dl-neo-methglhydrindamine. Isomeric salts of the type NR,R,H,." By G. Tattersall and F. S.Kipping. The P-methyl-a-hydrindamine, obtained by reducing methylhydrintl- oxime, has been separated into the two externally compensated bases of which it is composed by the use of d-bromocamphorsulphonic acid, which forms with each of the dl-bases a partially racemic salt. Tho externally compensated base, which is present in the larger quantity, is called met~~ylhydrindatiLine,the other being termed neo-methyl-hydp.ki?ccmine. Sfetlqlhydyindunzine bvomocnnapl~orsul~~l~olzate, C,of~,,N,C,oH,,OBr~SO,H,H,O, crystallises from dilute alcohol in hydrated, rhomboidal prisms, and, when dehydrated, melts at 160-165'.In dilute aqueous solution, this salt has a specific rotation [.ID = +51*5', and a molecular rotation [MID= + 235.5'. Those values are abnormal, because, since the salt contains dl-base, its moleciilar rotation should be that of the bromo- camphorsulphonic acid, namely, [MI, = + 270'. The benxopl derivative of methylhydrindamine melts at 151" ; the hgdi-ochloride, sulphute, and picrccte are also described. neo-Metl~?llhgdrindarnilze6roiriocan~~l~or~u~~~~onute, C',oH,,N,C,oH,,O~r~SO~H, crystallises from alcohol in large, anhydrous, transparent prisms melting at 194'; its specific rotation in dilute aqueous solution is [a]. = +58*9", whence [MI,-, = + 269.5'.This value is normal on the assumption that the salt is partially rncernic, and this was proved to be the case. The 6enxoyZ derivative of neo-methylhydrindamine melts at 169'. The hydrochloyide, sulphate, -and picmte of the neo-base are also described, dl-Methylhydrindamine bromocamphorsulphonate is not resolved by ordinary fractional crystallisation, but when treated with a mixture of warm alcohol and ethyl acetate a precipitate of the salt of the I-base is obtained, the salt of the d-base remaining in solution. 1-Methylhgdrindnmine bi.onLocan,p?~os.suZ~~~onuteseparates from water in long, anhydrous needles, the original melting point of which IS 230' ; its specific rotation in dilate aqueous solution is [.ID = i-45.7", and molecular rotation [NID= +209.4".The free base is lzvorotatory in dilute aqueous solution ; its hydrocl~lo~ide,which crystallises from water in needles or plates, has [ = + 56". d- Me thyZhylrindanaine bi.0 11 2 ocn n~phoT szc!pAonate i s in d isti ngui sbable 146 in appearance from the salt of the I-base ; it has an original melting point of 249'; its specific rotation is [.ID = +71', and molecular rota- tion [MI,= +326'. The free base is dextrorotatory in aqueous alcoholic solution. The formation of isomeric partially racemic salts of the same type as those formed from hydrindamine and d-bromocamphorsulphonic acid having been expected, and such isomerides not having been found in the original mixture of salts, the question of their existence was solved by decomposing each of the pure partially racemic salts and regenerating each separately from its components. Crystallisation of the products failed to reveal the presence of any isomerides, so that it' is concluded that isomeric partia.lly racemic a-and /3-salts of methy lhydrindamine and neo-methylhydrindamine do not exist.Isomeric #ah of the Type NR,R,H,.-On fractionally crystallising I-methylhydrindamine bromocamphorsulphonate, the melting point of the first fraction after about 20 crystallisations rose to 236', thus indicating that the original salt is a mixture. The pure salt, (m. p. 236') was then decomposed and regenerated from the same base and the same acid; fractional crystallisation of this product gave deposits with melting points gradually falling from 236' to about 224".The first and last fractions mere found to differ also in specific rotation, the first fraction (aI) having [a],= +47', [J!t]D= +216O, whilst the last gave [alD= +41', [MI,= + 188'. The existence of isomeric salts derived from I-methylhydrindamine and d-bromo-camphorsulphonic acid is thus proved. The isomeric salt melting at 236' is called the al-salt ; the second isomeride, which is named the pl-salt, could not be obtained in a pure condition. The d-methylhydrindarnine bromocamphorsulphonate obtained by the resolution of the partially racemic salt was treated in the same way as the salt of the I-base, and regenerated from its component acid and base ; the product mas fractionally crystallised.The specific rotations in dilute aqueous solution and the melting points of the first and last fractions were found to be as follows : First fraction (ad). [a]D = + 73', [MID= + 334'; m.p. 262'. Last fraction ...... + 67", [MI,= +307O; m. p. about 340'. Here, again, the existence of isomerides, distinguished as the ad-and @?-salts,is established, but the former only was obtained in a pure condition. The original L and d-components are, therefore, mixtures and consist of al-and PZ-, and ad-and /3d-salts respectively. If equal quantities of each are mixed before systematic crystallisation, the original partially racemic salt is obtained. If, however, equal weights of the 147 uZ-and ad-salts are mixed, a partially racemic salt, different from the original one, is obtained : M.1’.Crystalline form. [u]D in water. Original partially racemic salt ...... 160-165” Rhomboidal prisms. +51°. Synthetical partially racemic salt. .. 206” Rectangular prisms. +60“. The original partially racemic salt consists of the four components, namely, al-, pl-, ad-, and pd-salts, and corresponds with the partially racemic p-salt obtained from dl-hydrindamine and d-bromocamphor- sulphonic acid. 76. ‘;The action of liquefied ammonia on chromic chloride.” By W. R. Lang and C. M.Carson. When liquefied rtnimonia acts on violet chromic chloride, a salmon-coloured powder is produced, from which water extracts two distinct compounds, which are easily cryatallisable in vacuo and correspond in composition with the formuh Cr2CI,,12NH,,2H,0 and Cr2Cl,,10NH,. The former substance is yellow, whilst the latter has the colour of cobalt nitrate.The salmon-coloured powder, when kept :It 15O, yields both yellow and red crystals, but if heated to llOo it gives the red substance only. These compounds are completely decom- posed at 180’. 77. “Note on the action of inethylamine on chromic chloride.’’ By W. R. Lang and E. H. Jolliffe. Methylamine acting on violet chromic chloride produces a pink powder very readily soluble in water, from which it can be crystallised with difficulty owing to the rapidity with which chromium hydroxide separates out, The composition of the crystals corresponds with the formula Cr,CI,,lOCH;NH,. The pink compound, when heated at looo, yields a substance containing 8 mols. of ammonia; complete decomposition into chromic oxide occurs at 120’.78. Cholesterol. Preliminary note.” By R. H. Pickard and J. Yates. Owing to t’he recent piiblicatiori of the Hubilitationsclbrift (Freiburg) of A. Windaus bearing the above title, the authors wished to state that for over two years they have been investigating the constitution of cholesterol obtained from gallstones. The effects of nitric acid, fused potassium hydroxide, potassium clilorate and hydrochloric acid, 148 and alkaline permanganate solution on cholesterol have been studied in turn. The results hitherto obtained shorn that the cholesterol is composed of a rery stable, complex nucleus joined to a normal chain of some nineteen carbon atoms, inasmuch as arachidic acid, C,,H,,O,, is one of the products of its oxidation.The hydrocarbons obtained when cholesterol is treated with dehydrating agents and the action of alkalis on the halogen derivatives of cholesterol are also being investigated. 79. ‘I Hydrogen cyanide in fodder-plants.” By J. C. Briinnich. After the important discovery, by Messrs. Dunstan and Henry, of a glucoside ‘‘ Dhurrin ” (Proc. Roy. Soc., 1902, 70, 153) in the young plants of sorghum, which, on decomposition in presence of water, yields hydrogen cyanide, the author, on behalf of the Queensland Depart- ment of Agriculture, carried out a series of experiments in order to ascertain at what stages and conditions of growth the fodder-plants belonging to the sorghum family are most dangerous, Two varieties of sorghnm, and also a variety of maize, were grown on unmanured and heavily manured plots and analysed at vayious stages.The results show that sorghums should never be used as fodder in very young and immature stages of growth. 80. ‘‘Sulphocampholenecarboxylic acid.” By A. W. Harvey and A,Lapworth. When sulphocampholenecarboxylic acid (Proc., 1902, 18, 142) is oxidised with potassium permanganate, no oxalic acid is formed, and the product consists aImost entirely of acids which cannot be removed from a strongly acidified aqueous solution by ether, ethyl acetate, or acetone, and is therefore probably a mixture of sulphonic acids.A minute quantity of a volatile fatty acid, perhaps acetic acid, was detected. When the oxidation product is carefully fused with potassium hydroxide, it yields a mixture of carboxylic acids, the main constituent being identified as aa-dimothylglutnric acid, The metr3LyZ ester, CO~~le.~~~~~~i~*SO~.?(m. p. 192-1 93”), and _. the ethyl ester, C0,Et*F9H,,Br*S0,.$) (m.p. 101-102”), are very -easily obtained from the sultonecarboxylic acid (Zoc. cit.) by Fischer’s method. The carboxyl group is therefore attached to a hydrogenated carbon atom. The above observations indicate (I) that in the formation of sulpho-campholenecarboxylic acid from a-bromocamphor, scission has occurred between the carboxyl group and the trimethylcgclopentane nucleus, 149 (2) that the acid does not conhin the groiip :C:CH*CO,H, but probably iC*CH,-CO,H, (3) that itl is most probably related to p-and not to a-campholenic acid in spite of its optical activity, which is perhaps due to the presence of the sdphonic group.81. '' Optically active esters of @ketonic and ,&aldehydic acids. Part 111. Azo-derivatives of menthyl acetoacetate." By A. Lapworth. Menthyl p~e?zyZazoacetocccetate, C',H,*N,*CHAc-CO,*CIOHlD,from menthyl acetoacetate and phenyldiazonium sulphate in presence of sodium acetate, forms large, transparent crystals melting at 76-77'. In a 13 per cent. solution in benzene, it has initially [a],= -21-62', and this rises after some days to a constant value, [a],= -52.53'.The corresponding p-toZ?lZazo-compound, C6H,Me*N,*C'HAc*C0,*CloHls, melts at 86-81', and in benzene has [a],= -11-86" changing to -61.56' ;with phenylhydrazice, it yields p-metlryZ~l~eiz?ll-4.-nxo-l-phen?$--. CMe:N----3-meth1jl-5-pyrazolone, I yph which forms yellow orCH(IS,*C, H,Ne). C0 ' orange needles melting at 136-137". MeentJqZ p-bronzopl~eiiylaxoacetoacetate,C,H,Br~N,.CHAc~CO,~C,,H,,, melts at 119-121', and, in benzene solution, has [a],= -12'84" changing to -46.88' ;with phenylhydrazine, it gives rise to 4-b~onao-phenylaxo-1-pheizy 2-3-methP 2-5-py~cixo yhf e: N---NP I h , whichZone, CH(N,*C6H,Br) C0 melts at 152-153". iWentJqZ p-cltlorop~Lc,n~lc~xou~etocccet~~te,C,H,C:l~N,.CIIAc.CO,*CIIOHIS, melts at 103-105*, and in benzene has [ale= -15.43' changing to -55-79' ; with phenylhydrazine, it gives 4-p-cJ~Zo~o~~J~en~lazo-l-p~~~~~yZ-3-nieth~l-5-p~ruxoZoizemelting at 141-142".The mutarotation of the above compounds is accelerated by traces of bases or acids. By the action of diazo-oxides on the est,ers, formxzgl compounds are Formed. The following have been isolated, but the colour of their solutions is too intense to admit of the determination of their rotatory power. iWentJq2 pp'-di~~eti~yZphen~~o~n~axyZca~~boxyZate, C,H,R'le*NH*N C(N,C,H,Me)*CO,* C,,K, 9, forms dark red crystals with a blue reflex and meIts at 134-136'; meltsmenthyl p-bromopJien~Z-p'-s~ietl~yZ~~hen~lformcix~lc~trboxyZateat 149-15 1 " ; nzent hy I p-chZoropltenyI-pf-nieti~yZ~heny~omszcizyIcar60xylate melts at 145-14i0.The mutarotation of the azo-derivatives of menthyl acetoacetate is due to isodynamic change in virtue of the lability of the a-hydrogen 150 atom, and when this hydrogen atom is replaced by bromine the specific rotation becomes invariable. The a-bromo-derivatives, which represent a new class of azo-compounds, were made (1) by direct bromination of the above esters, (2) by the interaction of a diazo-oxide and menthyl a-bromoace toacet ate. JielztlqjZ phenyZ~xo-a-6~~~~oacetoacetccte,C,H,* N, CBI-AC.GO,*CI0Hl9, forms large, yellow crystals melting at 133-134'; it has [a]D= -82-45' in benzene. The corresponding p-tolyllazo-compound, CGH,Me.Nz.CBrAc*C0,.C,oH19,melts at 155-156' and has [a],= -85~95".The p-bl.onao~~~eizyZcLxo-compound, CBH,Br*N,*CBrAc*CO,*CloHIS, melts at 155' and has [aID= -73.45' ;the p-clJorop7LeuyZaxo-compound melts at 147-148'; it has [ a-JD= -67*6!O. The crystals of these four compounds exhibit anomdous dispersion of the optic axes, The following note has been received since the meeting : 82. '(The chemical reactions involved in the rusting of iron." ByW.R.Dunstan. In a lecture delivered before the Royal Artillery Institution at Woolwich, the substance of which was published in the Proceedings of tbat Institution (Vol. 26, 1899, No. 5) and also in Engineering, June 1, 1900, the author gave a general account of the results of an investiga- tion of the chemical process of rusting. This investigation, which was conducted with the cooperation of Dr.Jowett, was afterwards con-tinued, and with the assistance of XTr. E. Goulding extended, especially to the atmospheric corrosion of iron and steel, and a further account of the resiilts obtained was published in the Report (1900) of the Steel Rails Conitnittee OC the Board of Trade, of which the author was a member. Since then, the inquiry has been further extended, especi- ally with reference to the atmospheric corrosion of pairs of metals and to the elucidation of the general process. Val*ious circumstances have, however, delayed the completion of the work, and the present summary of the results is published pending the preparation of a fuller account of the investigation. It has been proved that whilst both liquid water and oxygen are necessary for the formation oE rust, the presence of carbonic acid is not essential, although it may accelerate the action.The well-known effect of alkalis and alkaline sslts in preventing the oxidation of iron has been hitherto attributed to the withdrawal of the carbonic acid. It has been found, however, that the phetlomenon is not due to this 131 cause, but to the establishment of conditions in which the production of hydrogen peroxide is ichibited. When highly purified iron, containing mere traces of impurity, is left in contact with dry gases (oxygen, carbon dioxide, mixtures of oxygen and carbon dioxide), rusting does not take place. In the presence of the same gases and water vapour, no rusting occurs so long as a constant temperature (34' in the actual experiments) is maintained, but if the temperature is allowed to fluctuate, liquid water condenses on the surface of the iron and rust is produced.It is thus shown that pure iron is not oxidised in presence of gases and water-vapour only, but that the presence of liquid water is necessary for rusting to take place. In another series of experiments, pieces of iron were left in contact with water saturated with a particular gas and with an atmosphere of the same gas above the solution. When hydrogen, carbon dioxide, or nitrogen which had been carefully freed from oxygen was employed, rusting did not occur, but if oxygen or a mixture of oxygen and carbon dioxide was used, oxidation took place.From these results, it is evident that for the formation of rust both oxygen and liquid water are required. In the experiments in which a mixture of oxygen and carbon dioxide was used, the results observed indicated that in this case a secondary action proceeds simnltaneously. In order to investigate the influence of solutions of various salts on the production of rust, small pieces of highly purified sheet iron were enclosed with the different solutions in sealed glass tubes, the space above the solution in each case being filled with pure oxygen. The following substances mere found to prevent to a greater or less extent the formation of rust :sodium carbonate, ammonium carbonate, borax, disodium hydrogen phosphate, calcium hydroxide, ammonia, potassium dichromate, potassium ferrocyanide, chromic acid, sodium nitrite, and potassium carbonate.Rusting occurred in the presence of the follow- ing compounds : sodium chloride, potassium chlorate, ferrous sulphate, potassium ferricganide, potassium nitrate, and sodium sulphate. The reagents which prevent the rusting of iron are those in presence of which decomposition of hydrogen peroxide takes place and which are consequently inimical to its formation. There can be little doubt, therefore, that hydrogen peroxide plays an important part in the chemical process of rusting. By the direct action of hydrogen peroxide on metallic iron, a red basic ferric hydroxide, identical with ordinary rust, is rapidly produced, and it is found that in general those metals rust in air which are oxidised by hydrogen peroxide, whilst those metals which are not oxidised by hydrogen peroxide do not rust in air.Iron, zinc, and lead are examples of the first class, and the rusting of all these metals is stopped by contact with substances which prevent 152 the formation of hydrogen peroxide. Copper, silver, and nickel are examples of the second class; these metals do not rust in air and are not oxidised by hydrogen peroxide. The analysis of a number of specimens of iron rust has shown that its composition may be represented by the formula Fe,O,(OH),. The chemical reactions concerned in the process of rusting may therefore be represented by the following equations : Fe +0, + H,O = FeO +H,O,.2Fe0 + H,O, = Fe,O,(OH),. The presence of water in the liquid state is essential alike for the occurrence of rusting and for the formation of hydrogen peroxide. In the case of certain metals, notably that of zinc, hydrogen peroxide can be detected during the process of rusting. It has no5 heen possible, however, to detect with certainty the presence of hydrogen peroxide during the rusting of iron. This may be due to the fact, previously mentioned, that iron is very rapidly oxidised by hydrogen peroxide with formation of rust, so that under ordinary conditions the hydrogen peroxide is quickly destroyed. The influence of certain other reactions on the process of rusting has been studied and may be summarised as follows : (I) The direct decomposition of water by metallic iron with libera- tion of hydrogen can take place only at a relatively high temperature and is not affected by the presence of alkaline salts, such as sodium carbonate.(11) The action of aqueous carbonic acid on iron in the absence of oxygen results-in the liberation of hjdrogen and formation of ferrous carbouate or bicarbonate. If oxygen is present, the ferrous salt subsequently undergoes oxidation, the rust obtained in this case con- taining a varying amount of carbonate. (111)Electrolytic action occurs when the iron is impure or when another metal is present. The electropositive metal suffers oxidation and hydrogen gas is evolved. This action is not prevented by the presence of sodium carbonate.153 ADDITIONS TO THE LIBRARY. I. Doncbtiom. Hartley, .H. B. Polymorphism. pp. 29. From the Author. Frankland. Autobiographical sketches from the life of Sir Edward Frankland, K.C.E., F.R.S. pp. 480. From Mrs. West and 31rs. Colenso. II. By Yzirclhccs 9, Georgievics, G. von. Chemistry of dyestuffs, translated from the second German edition by Charles Salter. pp. 402. London 1903. Klocker, A lb. Fermentation organisms. A laboratory hand-book. Translated from the German by G. E. Allan and 5. H. Millar, and revised by the author. pp. 392. ill. London 1903. International Catalogue of Scientific Literature. First Annual Issue. C. Physics, Part I1 ; G. Mineralogy, including petrology and crystallography, 2 vols.London 1903. Richter, V. von. Chemie der Kohlenstoff verbindungen oJer organische Chemie. Zehnte huflage. Eearbeitet von R. Anschutz in Gemeinschaf t rnit G. Schrater. Vol. I. Die C'henzie der Fettkoypr. pp. 746. ill. Bonn 1903. Wolfrum, A. Chemisches Praktikum. Teil 11. Priiparative und fabrikatorische ubungen. pp. 575. ill. Mit einem Atlas. Leipzig 1903. --Die Grundzuge der chemischen Didaktik. Eine Sbudie iiber das Studium Chemie und den Laboratoriumsunt erricht. pp. 147. Leipzig 1903. Betti, Mario. Benaftossaxine e coniposti a6ni contenenti radicali aldeidici e chetonici wisti (From the Gazr. Clzim. ItaZ., 33,pt. I, 1903.) Sulla f unzione delle basi P-naftol-aldaminiche. (Fron~the G'axz. Chinz. Ital., 33,pt. I, 1903.) -Roazione generale di condensazione fra p-naftolo, aldeidi e amine.(Prom the Gcczx. Chi172. Ital., 33,pt. I, 1903.) Clemm, W. K. Die Gallensteinkrankheit, ihre Hiiufigkeit, ihre Entstehung, Verhiitung und Heilung durch innere Behandlung. Berlin 1903. Garland. La industria del petr6leo en el Per6 en 1901. (Being Boletin del Cuerpo de Ingenievos de illinccs del Peru No. 2.) 154 Hall, A. D. The continuous growth of mangels for twenty-seven years on the same land, Barn Field, Rothamsted. (From the Jown. of the Royal Agrr.icultura2 Societp of EngZand, uol. 63,1909.) Langtvorthy, C. F. The functions and uses of foods. (Being U.S. Dept. of Agric. O’ce oj*Zxperiment Stations Circular 46.) National Physical Laboratory. Reports for years 1901-2.RESEARCH FUND. A meeting of the Research Fund Committee will be held in June. Applications for grants, to be made on forms which can bo obtained frorn the Assistant Secretary, must be received on or before June 8th. At the next ordinary Meeting, on Thursday, June 4th, 1903, at 8p.m., the following papers will be communicated : (‘Irnino-ethers corresponding to ortho-substituted benzenoid amines.” By G. D. Lander and F. T. Jewson. ‘‘Formation of an anhydride of campl~oryloxime.” By T. M. Lowry. “The mutarotation of glucose as influenced by acids, bases, and salts.” By T.M. Lowry. -‘‘The solubility of dynamic isomerides.” By T.hl. Lowry. ‘I Isomeric partially rncemic salts containing quinquevalent nitrogen. Part X. The four isomeric hydrindamine d-chlorocamphor- sulphonates, NR1R2H3.” Ey F. S. Kipping. “Isomeric compounds of the type NR,R,H,.” By F. S. Kipping. ‘‘The hydrolysis of ethyl mandelate by the fat splitting enzyme, lipase.” By H. D. Dakin. K. CLAY ASD SOPiS, LTD., BREAD ST. HILL, E.U., AND BUNOAY, SUFFOLK.
ISSN:0369-8718
DOI:10.1039/PL9031900139
出版商:RSC
年代:1903
数据来源: RSC
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